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INTERNATIONAL SOCIETY FOR ROCK MECHANICS Internationella Samfundet För Bergmekanik

NEWS JOURNAL www.isrm.net

The 2010 Annual Review, the 2007–2011 ISRM Board‘s Achievements, Rock Stress Technical Articles, and Invitation to the 12th ISRM Congress—see Back Cover

Forces from adjacent tectonic plates acting on the Eurasian Plate, from Xie Furen, see pages 39–43

Annual Review 2010

Rock Stress

ISRM Information, the Secretary-General’s Report, Symposia reports, plus Regional and Commission reports

Technical articles from the ISRM Rock Stress Symposium held in Beijing, China, in 2010

Volume 13, December 2010

See Table of Contents on Page 3


Editor-in-Chief:

ISRM Secretary-General:

Prof John A Hudson

Dr Luis Lamas

President, ISRM Imperial College and Rock Engineering Consultants, UK john.a.hudson@gmail.com

LNEC Avenida do Brasil, 101 P-1700-066 Lisbon, Portugal Tel: +351 21 844 3419 Fax: +351 21 844 3021 secretariat.isrm@lnec.pt

Assistant Editor:

ISRM Secretariat: Sofia Meess

Dr Nuno Grossmann

LNEC Avenida do Brasil, 101 P-1700-066 Lisbon, Portugal Tel: +351 21 844 3419 Fax: +351 21 844 3021 secretariat.isrm@lnec.pt

LNEC Avenida do Brasil, 101 P-1700-066 Lisbon, Portugal Tel: +351 21 844 3388 grossmann@lnec.pt

Editor’s Introduction to this Volume ference‘, which is a category that we have recently introduced for meetings with a strongly focused theme. We now look forward to the 12th ISRM Congress which will be held from 18-21 October 2011 in Beijing, see back cover of this Issue. At the Congress, Dr Nick Barton will be presenting the Müller Lecture— with the title ―From Empiricism through Theory to Problem Solving in Rock Engineering‖, see page 18. During the 2011 Congress, the ISRM Presidency will pass from myself to Professor Xia-Ting Feng of China and so I have taken the opportunity now of listing the achievements of the 2007-2011 ISRM Board on page 6. We began in 2007 with an ISRM modernisation programme and I am pleased to say that we have inaugurated/accomplished many things, including a survey of ISRM members, the creation of ISRM Fellows, the OnePetro website ability to download ISRM Symposium papers, inclusion of downloadable lectures on the ISRM website, initiating the annual ISRM field trip, and the creation of a Young Members‘ Presidential Group.

We have had an interesting and successful 2010 conference year. 1. European Regional Symposium EUROCK 2010: Rock Mechanics in Civil and Environmental EngineerJohn A Hudson ing, June 2010, in Lausanne, Switzerland (described on page 27). 2. Specialised Conference: 3rd International Workshop on Rock Mechanics and Geo-Engineering in Volcanic Environments, May–June 2010, in Tenerife, Spain. 3. Specialised Conference: 5th International Symposium on In Situ Rock Stress, August 2010, in Beijing, China (see the technical articles starting on page 38). 4. ISRM International Symposium ARMS 6: Advances in Rock Engineering, October 2010, in New Delhi, India (see the report on page 15). 5. South American Regional Symposium: VII SouthAmerican Rock Mechanics Congress, December 2010, in Lima, Peru (described on pages 29 & 30). I was able to attend all of these, except the second one, and can report that they were most rewarding, thanks to the valiant efforts of both the respective organisers and the participants. Note that the second and third of these meetings were a ‗Specialised Con-

John A Hudson, 2


Table of Contents

The 2010 ISRM Year The 2007–2011 ISRM Board Achievements of the 2007–2011 Board The ISRM Digital Library The 2010 ISRM Year 2010 ISRM Membership Indicating the Members/Country Reports of ISRM Board and Council Meetings 2010 Report of the ISRM Secretary-General for 2010 th 6 Asian Rock Mechanics Symposium, ARMS6 ISRM Membership: Joining, Benefits and Fees Organising ISRM Symposia and ISRM Events Interview: Nick Barton (2010 Müller Award winner) by Ivan Vrkljan 2013 Rocha Medal Submissions: Application Deadline 31 Dec. 2011 Record of the 2nd Annual ISRM Technical and Cultural Field Trip 2010 Activity Report by ISRM Vice-President for Africa 2010 Activity Report by ISRM Vice-President for Asia 2010 Activity Report by ISRM Vice-President for Australasia 2010 Activity Report by ISRM Vice-President for Europe 2010 Activity Report by ISRM Vice-President for N. America 2010 Activity Report by ISRM Vice-President for S. America Introduction to the ISRM Commissions Geophysics Commission Report Education Commission Report Mine Closure Commission Report Ancient Sites Commission Report

Radioactive Waste Commission Report Rock Dynamics Commission Report Design Methodology Commission Report Rock Spalling Commission Report Testing Methods Commission Report

4 6 7 8 9 10

34 35 35 36 37

Technical Articles on In Situ Rock Stress

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Introduction to the Technical Articles 38 Tectonic Stress and Earthquakes 39 in China—F. Xie A Global Stress Interpretation Model— 44 L. N. Lamas, J. Muralha and B. Figueiredo Borehole Wall Stress Relief Method 50 (BWSRM)—X. R. Ge and M. X. Hou Rockburst Prediction in the Carrara 51 Marble, Italy—M. Coli, E. Livi, P. Berry, A. Bandini, Manchao He and Xuena Jia Present-Day Stress State in South-East 55 Korea—C. Chang and T.S. Kang

15 16 17 18 20 21 22

*****

23

ISRM Corporate Members Invitation to the 12th ISRM Congress

25 27 28 29 31 32 32 33 33

3

58 60


The 2007-2011 ISRM Board John A Hudson, UK President

Francois Malan Vice-President, Africa

Professor John A Hudson Emeritus Professor, Imperial College, London, and Independent Consultant, Rock Engineering Consultants Tel: (+44) 1707 322819

Dr Francois Malan PO Box 7379 Westgate Republic of South Africa 1734 Tel.: (+27) 11 482 8838 Fax: (+27) 11 482 8839

john.a.hudson@gmail.com

francois.malan@groundworks.co.za

Abdolhadi Ghazvinian Vice-President, Asia

Anthony Meyers Vice-President, Australasia Dr Anthony Meyers PO Box 210 Rundle Mall Adelaide South Australia 5001 Australia Tel.: (+61) 8 8376 9096 Fax: (+61) 8 8376 9096

Dr Abdolhadi Ghazvinian Tarbiat-Modares University Dept of Mining Engineering Faculty of Engineering PO Box 14155-4838 Tehran, Iran Tel.: (+98) 21 2578 470 Fax: (+98) 21 2578 470

tony@rocktest.com.au

abdolhadi@yahoo.com

Derek Martin Vice-President,

Nuno Grossmann, Vice-President, Europe

North America

Dr Nuno Grossmann LNEC Av. do Brasil, 101 1700-066 Lisboa Portugal Tel.: (+351) 21 844 3388 Fax: (+351) 21 844 3026

Prof. Derek Martin University of Alberta Dept Civil & Environmental Engineering, Edmonton AB T6G 2W2 Canada Tel.: (+1) 780 492 2332 Fax: (+1) 780 492 8198

derek.martin@ualberta.ca

grossmann@lnec.pt

4


Álvaro J. GonzalezGarcia Vice-President, South America

Xia-Ting Feng Vice-President At Large Prof. Xia-Ting Feng Institute of Rock and Soil Mechanics, The Chinese Academy of Sciences Xiaohongshan Wuchang Wuhan 430071, China Tel.: (+86) 27 87198913 Fax: (+86) 27 87197386

Prof. Álvaro J. GonzalezGarcia Carrera 57, No. 172-44 Bogotá D.C., Colombia Tel.: (+57) 1 6720297 Fax: (+57) 1 6724251

ajgon@cable.net.co

xtfeng@whrsm.ac.cn

Claus Erichsen Vice-President

Luís Lamas Secretary-General

At Large Dr Claus Erichsen WBI Prof. Dr.-Ing. W. Wittke Beratende Ingenieure für Grundbau und Felsbau GmbH Henricistr. 50 Aachen 52072, Germany Tel.: (+49) 241 88 Fax: (+49) 241 8898733

Dr Luís Lamas Secretary General, ISRM LNEC, Av. do Brasil, 101 1700-066 Lisboa Portugal Tel.: (+351) 218443419 Fax: (+351) 218443021

secretariat.isrm@lnec.pt

wbi@wbionline.de

The main thrust of the 2007-2011 ISRM Board has been ‗modernisation‘, see next page— a key element of which is enhanced communication between all ISRM Members. The email addresses of your regional Board representatives, together with the President and Secretary-General, are given above. We welcome contact/inquiries/suggestions from current and potential ISRM Members. Note, however, that a new 2011–2015 ISRM Board under the Presidency of Professor Xia-Ting Feng will be inaugurated at the 12th ISRM Congress in Beijing in October 2011.

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Achievements of the 2007-2011 ISRM Board The list below indicates the new initatives stimulated by the ‗Modernisation‘ theme and implemented by the ISRM Board during the 2007-2011 period (some of which had to be approved by the ISRM Council).  Survey of ISRM Members (April 2008)  Report of the ISRM Commission on Mine Closure uploaded and available from the ISRM website  Erik Eberhardt‘s lectures on rock mechanics inaugurated as a series of downloadable ISRM Lectures on rock

mechanics and rock engineering from the ISRM website  Historical videos of the ISRM and videos of the Keynote Lectures of ISRM conferences accessible from the                       

ISRM website Launch of the ISRM Virtual Library hosted by the OnePetro website, see opposite page New ISRM slide collection accessible online (to be completed in 2011) Creation of the ISRM Fellows and Ex-Board Members‘ Forum, to meet at the Congresses and provide advice Creation of pre-Commissions (i.e., early organisation of Commissions for the next Board‘s tenure period) Nature and frequency of the ISRM Regional Symposia have been changed, and ISRM Specialised Conferences have been created as a new type of ISRM sponsored event (revision of By-Law No. 5) Creation of Proxime Accessit certificates for up to two Rocha Medal runners-up (revision of By-Law no. 7) Creation of ISRM Fellows (revision of the Statutes) Creation of the ISRM Annual Lecture Planning the ISRM 50th year anniversary celebrations with associated logo and book (these celebrations start at the ISRM Congress in Beijing in October 2011 and continue to the Stockholm EUROCK meeting in 2012 Pdfs of ISRM membership certificates available Creation of Young Members‘ Slide Show Competition ISRM Lecture Tour in China in May 2009 Creation of the Annual ISRM Technical and Cultural Field Trip, the first one being to the Carrara marble quarries and the Florence region, Italy, 2009 led by Massimo Coli 2nd ISRM Technical and Cultural Annual Field Trip to the Lausanne region, Switzerland, 2010, led by Christophe Bonnard ISRM Lecture Tour in Colombia and Peru, 2010 Creation of the ITA-ISRM Joint Action Group on ―Site Investigation Strategy for Rock Tunnels‖ with the aim of preparing a Guidance Document Participation (with ISSMGE and IAEG) in the reconfiguration of FedIGS to a less cumbersome and more flexible operation Start of the ISRM electronic Newsletter (March 2008) and continuation with four Newsletters/year Launch of a CD containing pdfs of all the ISRM News Journal Issues 1996 to 2008, and making these available from the ISRM website Creation of the ISRM Young Members‘ Presidential Group Creation of an all-language inclusive ISRM policy, but with English as the only official language (revision of the Statutes). 16% increase of the individual ISRM Members, from 5354 in 2007 to 6210 in 2010 New ISRM membership management system

I should like to take this opportunity to thank the 2007-2011 ISRM Board Members, Claus Erichsen, Xia-Ting Feng, Abdolhadi Ghazvinian, Álvaro J. Gonzalez-Garcia, Nuno Grossmann, Luis Lamas, Francois Malan, Derek Martin and Tony Meyers for their inspiration, resourcefulness and support in the generation and implementation of all the initiatives listed above. John A. Hudson, ISRM President 2007–2011

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The ISRM Digital Library (abridged ppt presentation) One of the most important achievements in the list on the opposite page is the October 2010 launch of the ISRM Digital Library Presented on this page are a few key slides describing members‘ access to this facility. The complete PowerPoint presentation is available on the ISRM website.

www.OnePetro.org

Luis Lamas, Portugal, ISRM Secretary-General (secretariat.isrm@lnec.pt)

There is no charge to ISRM members for this facility: up to 100 downloads/year

7


The 2010 ISRM Year Prepared by Luis Lamas, Portugal, ISRM Secretary-General (secretariat.isrm@lnec.pt) 2010

ISRM-Sponsored Events

Key Events

January February

South America Lecture Tour in Colombia and Peru

March

Interim Board meeting in Bogota, Colombia

Publication of the digital ISRM Newsletter No.9

April

May

3rd International Workshop on Rock Mech-anics and Geo-Engineering in Volcanic Environments, Tenerife, Spain—an ISRM Specialised Conference

FedIGS Board meeting in London, UK Signature of the Agreement between the ISRM and Taylor & Francis Group PLC for the right to publish the Proceedings of ISRM-sponsored Conferences Signature of the Document Delivery Royalty Agreement between the Society of Petroleum Engineers Inc. and the ISRM

2nd ISRM annual technical and cultural field trip in Switzerland Publication of the digital ISRM Newsletter No.10 June

EUROCK 2010: Rock Mechanics in Civil and Environmental Engineering, Lausanne, Switzerland—an ISRM Regional Symposium

July

August

5th International Symposium on In Situ Rock Stress, Beijing, China—an ISRM Specialised Conference

September

Publication of the digital ISRM Newsletter No.11 Launching of the ISRM Digital Library

October

ARMS 6: International Symposium on Advances in Rock Engineering, New Delhi, India

ISRM Council meeting in New Delhi: Revision of the ISRM Statutes  Dr Nicholas Barton selected as recipient of the Müller Award 2011  Dr Jan Christer Andersson presents 2010 Rocha Medal paper at the New Delhi Symposium  Dr Dohyun Park from Korea selected as recipient of Rocha Medal 2011  Montréal, Canada selected as the venue for the 13th ISRM International Congress in 2015

November

December

VII South-American Rock Mechanics Congress, Lima, Peru—an ISRM Regional Symposium

Publication of the digital ISRM Newsletter No.12

8


2010 ISRM Membership Prepared by Luis Lamas, Portugal, ISRM Secretary-General (secretariat.isrm@lnec.pt)

9


Reports of ISRM Board and Council Meetings, 2010 Luis Lamas, Portugal, ISRM Secretary-General (secretariat.isrm@lnec.pt)       

ISRM BOARD MEETING, Bogotá, February 2010 This interim Board meeting was held in Bogotá, Colombia, on 8 February 2010 and was chaired by the First Vice President, Dr Nuno Grossmann, due to the unexpected illness of the ISRM President, Prof. John Hudson. It was attended by the Vice-Presidents of the respective geographical areas except for the Vice President for North America, and by the Vice-President-at-Large, Prof. Xia-Ting Feng, and by the Secretary-General. The subjects covered were as follows:  The main decisions taken after the last Board meeting  Brief presentation by the Vice-Presidents and the Secretary-General  The situation with FedIGS  Pre-Commission on Petroleum Geomechanics  Revision of the ISRM Statutes to be submitted to the Council in New Delhi  Revision of the ISRM Guidelines on sponsored events  Approval of the EUROCK 2012 in Sweden  New sponsorship applications: the 7th South American Rock Mechanics Congress, to be held in Lima, Peru, in December 2010, and EUROCK 2013, to be held in Wroclaw, Poland in September 2013  Brief review of the forthcoming ISRM-sponsored events: the ISRM Lecture Tour in Bogotá and Lima in February 2010; the 3rd International Workshop on Rock Mechanics and Geo-engineering in Volcanic Environments, to be held in Tenerife, Spain in May-June 2010; EUROCK 2010 to be held in Lausanne, Switzerland in June 2010; the 5th International Symposium on In Situ Rock Stress, to be held in Beijing, China in August 2010; the 6th ARMS in New Delhi, India in October 2010  Review of the ISRM International Congress, Beijing, China in October 2011  Page allocation for the ISRM Congress  Celebration of the 50 Years of the ISRM 2011-2012  Volume 2 of the Blue Book (i.e., the Orange Book)  Modernisation initiatives

Rocha Medal 2011: selection of the winner Strategy for the ISRM Fellows‘ Programme Strategy for the ISRM Annual Lecture Ex-Board members‘ Forum Celebration of the 50 years of the ISRM Rock Stress Conferences Report on the progress of ARMS6 to be held in India in October 2010, of the 7th South American Rock Mechanics Congress, to be held in Lima, Peru in December 2010, of the 12th International Congress to be held in Beijing, China in 2011, and of EUROCK 2012, to be held in Stockholm, Sweden in May 2012.  Discussion on the ISRM endorsement of EUROCK 2013 and selection of its venue  Information by the Secretary-General of endorsement by ISRM of the 2nd ISRM International Young Scholars‘ Symposium on Rock Mechanics to be held in Beijing, China in October 2011, and of the application for EUROCK 2014 to be held in Vigo, Spain, in May 2014  Presentation on the initiatives for the modernisation of the ISRM Special attention was given to the initiatives underway to modernise the ISRM, each Board member having reported on the following assigned topics, indicating the strategy for attaining the proposed objectives:  Prizes and certificates (President)  Communication with members, Newsletter, News Journal (President, V-P Europe, Secretary-General)  Availability of literature (V-P Africa)  Website strategy (V-P Asia)  Membership numbers and improving the benefits to members (V-P Australasia)  Major technical issues (V-P North America)  Strategy for interaction with other Societies (V-P South America)  Lecture tours and educational material (V-P-at-Large Dr Claus Erichsen)  Content of ISRM International Symposia and Conferences (V-P-at-Large Prof. Xia-Ting Feng)

ISRM BOARD MEETING, New Delhi, October 2010 This meeting was held in conjunction with the 2010 ISRM International Symposium Advances in Rock Engineering (6th ARMS), in New Delhi, India, on 23 October 2010. The meeting was chaired by the President of the ISRM, Prof. John Hudson, and was attended by the Vice-Presidents of the respective geographical areas except for the Vice President for North America, and by the two Vice-Presidents-at-Large, and by the Secretary-General. The subjects covered were as follows:  Report by the President on the main decisions taken after the last Board meeting  Brief presentations by the President, and the VicePresidents  Brief presentation by the Secretary-General on finances and the budget for 2011  Commissions and new Pre-Commissions

ISRM COUNCIL MEETING 2010 The ISRM held its Council meeting in conjunction with ARMS 6 in New Delhi, India, on 24 October 2010. 36 of the 47 National Groups were represented and three Past Presidents were present. An ITA representative and most of the ISRM Commission Chairmen attended the meeting. Report of the President The President referred to the nine ISRM Commissions currently active and the two Pre-Commissions organised in advance, so as to be fully prepared at the beginning of their 2011-2015 term. He stressed the initiatives to modernise the Society, applauded the success of the electronic Newsletter, and noted the increasing number of ISRM Members. He also reported on the tasks undertaken by the Board Members regarding the modernisation of the Society.

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       

Reports of the Regional Vice-Presidents Each Vice-President presented a report on the activities carried out in the respective geographical areas (these reports are included in this Issue of the News Journal, pages 22–30). Report of the Secretary-General The Secretary-General presented his report, concentrating on the evolution of the ISRM membership, the exclusion of Ghana, Hungary and Mexico from the ISRM, the Rocha Medal winner, the News Journal and Newsletter, the ISRM website and the recently launched Digital Library. This report is included in this issue of the News Journal, pages 12–14.

Commission on Preservation of Ancient Sites Commission on Radioactive Waste Disposal Commission on Rock Dynamics Commission on Rock Engineering Design Methodology Commission on Rock Spalling Commission on Testing Methods Pre-Commission on Petroleum Geomechanics Pre-Commission on In Situ Stress and Earthquakes

ISRM Sponsored Meetings Beijing was confirmed as the venue for the 2011 ISRM Board meeting, to be held in October, in conjunction with the 12th ISRM Congress. The organisers of the ISRM sponsored events presented the progress on their organisation:  23–27 October 2010, New Delhi, India: ARMS 6, International Symposium on Advances in Rock Engineering, the 2010 ISRM International Symposium  16–21 October 2011, Beijing, China: Harmonising Rock Mechanics and the Environment, the 12th ISRM International Congress  2–4 December 2010, Lima, Peru: 7th South American Rock Mechanics Congress, an ISRM Regional Symposium  28–30 May 2012, Stockholm, Sweden: EUROCK 2012, Rock Engineering and Technology for Sustainable Underground Construction, an ISRM International Symposium  21–26 September 2013, EUROCK2013, Wroclaw, Poland: an ISRM Regional Symposium

Accounts of 2009 and Budget for 2011 The ISRM accounts for 2009 and the Budget for 2011 were approved. Approval of Amendments to the ISRM Statutes The ISRM Statutes were revised by the Council in three aspects. French and German will no longer be used as official languages, English remaining as the official language. Specialised Conferences were introduced as a new type of ISRM-sponsored event, focused on specific topics. The category of Fellow was created: this will be conferred on individuals who have achieved outstanding accomplishments in the field of Rock Mechanics and/or Rock Engineering and who have contributed to the professional community through the ISRM. Announcement of the 2011 Müller Award recipient Three nominations were received: Dr. Nick Barton, Prof. Richard Goodman and Prof. Peter Kaiser, with Dr. Barton being selected as the 6th Müller Award winner. He will receive the award and deliver the Müller Lecture at the 12th ISRM Congress in Beijing, in October 2011. The Müller Award honours the memory of Prof. Leopold Müller, the founder of the ISRM, and is made every four years in recognition of distinguished contributions to the profession of rock mechanics and rock engineering.

Selection of the venue of the 13th ISRM International Congress in 2015 Two applications were received to host the ISRM Congress in 2015: from Canada, in Montréal; and from India, in Agra. The proposal received from CARMA, the Canadian Rock Mechanics Association ,was selected by the ISRM Council. The 13th Congress of the ISRM, “Innovations in Applied and Theoretical Rock Mechanics”, will take place on 29 April to 6 May 2015 and will be chaired by Prof. Ferri Hassani.

Announcement of the Rocha Medal 2011 winner The Council was informed that the ISRM Board decided to award the Rocha Medal 2011 to Dr. Dohyun Park, for his thesis “Reduction of Blast-induced Vibration in Tunnelling using Barrier Holes and Air-deck”. Dr. Park will receive the award at the 12th ISRM Congress in Beijing, in October 2011. The Board also awarded one runner-up Proxime Accessit certificate to Dr. Bo Li, from China, for the thesis “Coupled Shear-flow Properties of Rock Fractures”. ISRM Commissions The President informed the meeting of the nine existing Commissions and two Pre-Commissions and emphasised their production of significant new products. Reports on their activity were presented by the respective Chairmen or their representatives:  Commission on Education  Commission on Geophysics  Commission on Mine Closure

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Report of the ISRM Secretary-General for 2010 Luis Lamas, Portugal, ISRM Secretary-General (secretariat.isrm@lnec.pt) National Groups 1. National Groups and Membership The Board was happy to approve the Associaci贸n Costarricense de Geotecnia (ACG) and the Associaci贸n Boliviana de Geomec谩nica (BAG) as the ISRM National Groups representing Costa Rica and Bolivia. The current number of ISRM National Groups is 47, as the result of the exclusion of Ghana, Hungary and Mexico, due to lack of payment of the membership fees for over three years. The table on page 9 presents the situation regarding ISRM membership, per country and per region, in 2010. The present numbers of individual (ordinary and corresponding) and corporate members are (as at early 2011): Individual Members Africa Asia Australasia Europe N America S America

43

45

45

45

45

46

47

47

46

46

46

48

49

48

47

40 30 20 10 0 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

The distribution of individual and corporate members in each geographic region is shown below. National Groups

Corporate Members

296 1,825 346 3,002 653 171 6,293

TOTAL

50

3 69 2 60 2 0 136

N America; 653; 10%

S America; 171; Africa; 296; 5% 3%

Asia; 1825; 29%

When compared with the figures presented in 2009, this corresponds to an increase of 301 individual members (5.0%). The large increase in the Indian National Group, 304 to 550 members, and in the Chinese National Group from 502 to 554 members should be noted. The graphics below present the evolution of the number of ISRM members and National Groups in the last 15 years.

Australasia; 346; 5%

Europe; 3002; 48%

Individual Members 7000 6000

5992 5540 5588 5123

5000

4978

4804 4789

5022

4998 4755 4853

5190

6293

Corporate Members

5354 5498

S America; 0; 0%

4000

N America; 2; 1%

3000 2000

Africa; 3; 2%

1000 0 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Europe; 60; 44%

Corporate members 200 150

187

174

167

164

Asia; 69; 52%

167

158 136

132

136

130

133

129

142 125

136

100

Australasia; 2; 1%

50 0

The following graphic shows the recent evolution of the number of individual members in each geographic region. In the past year there was an increase in the number of members from all regions, except Africa and North America that had a slight decrease. Asia has been the fastest growing region in-

1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

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Report of the ISRM Secretary-General for 2010 (cont.) 3500 3002

2982

3000

2827

2814 2631

2639

2849

2671

2500

Africa Asia

2000

Australasia

1825 1539

1500 1000

N America

1318

889

844

S America

1148

1049

1004

712

500

517

499 274

340359

340328

327 180

140

303 122

585

562

502 361

302 101

369

303325

303320 123

132

296 136

 

653

576

Europe

346 171

Mechanics in Civil and Environmental Engineering, June 2010, in Lausanne, Switzerland. Specialised Conference: 3rd International Workshop on Rock Mechanics and Geo-engineering in Volcanic Environments, May-June 2010, in Tenerife, Spain. Specialised Conference: 5th International Symposium on In Situ Rock Stress, August 2010, in Beijing, China. ISRM International Symposium ARMS 6: Advances in Rock Engineering, October 2010, in New Delhi, India. South American Regional Symposium: VII SouthAmerican Rock Mechanics Congress, December 2010, in Lima, Peru.

0 2003

2004

2005

2006

2007

2008

2009

2010

The following ISRM conferences were approved during the same period:  Specialised Conference: 2nd International Young Scholars Symposium on Rock Mechanics, October 2011, in Beijing, China.  International Symposium EUROCK 2012: Rock Engineering and Technology, May 2012, in Stockholm, Sweden.  European Regional Symposium EUROCK 2013: Application of Rock Mechanics to Civil and Mining Engineering, September 2013, in Wroclaw, Poland.

the ISRM, and has doubled its number of members in the last six years. 2. Payment of fees The situation of the National Groups as regards payment of fees is as follows: Unpaid in 2009: Denmark Unpaid in 2010: Canada; Czech Republic; Denmark; Indonesia; Nepal; Norway; Peru; Switzerland; USA.

5. Rocha Medal During the New Delhi International Symposium, the Rocha Medal Award Committee selected, as the winner of the 30th prize (Rocha Medal 2011), the thesis submitted by Dr Dohyun Park, entitled ―Reduction of Blast-Induced Vibration in Tunnelling Using Barrier Holes and Air-deck‖. This work, selected from among nine shortlisted theses, had been submitted by the Korean Society for Rock Mechanics. The award will be conferred in October 2011, during the 12th ISRM International Congress in Beijing, China.

3. Federation of International Geo-engineering Societies: FedIGS Since the Cairo meeting in February 2009, the FedIGS Board met in Ghent, Belgium, in November 2009, and in London, UK, in May 2010. From the ISRM, the Ghent meeting was attended by the First Vice-President, the immediate PastPresident and the Secretary-General. The London meeting was attended by the President, the immediate Past-President and the Secretary-General. The items considered at the meetings dealt with the development of the FedIGS activities. At the London meeting, the three Presidents of the ISRM, the ISSMGE, and the IAEG made a series of agreed recommendations for re-configuring FedIGS to a leaner, more effective Federation. Due to the resignation of Prof. William van Impe as FedIGS President, the Board unanimously agreed that the ISRM Immediate Past-President, Prof. Nielen van der Merwe, will act as Chairman of the Federation until May 2011, when the situation will be reviewed at the next FedIGS meeting.

6. Müller Award Three nominations were received for the 6th ISRM Müller Award: Dr Nicholas Barton, nominated by the National Group of Colombia, Prof. Richard Goodman, nominated by the National Group of the USA, and Prof. Peter Kaiser, nominated by the National Group of Canada. During the New Delhi International Symposium, the ISRM Council selected Dr Nicholas Barton as the 2011 Müller Award recipient. The award will be conferred in October 2011, during the 12th ISRM International Congress in Beijing, China where Dr Barton will deliver the Müller Lecture.

4. ISRM-sponsored meetings The Secretariat provided assistance to the Vice Presidents and National Groups in the formulation of agreements and the spreading of information regarding the different ISRM Sponsored Meetings. Since the last ISRM Council meeting in Hong Kong, May 2009, four ISRM sponsored conferences were held:  European Regional Symposium EUROCK 2009: Rock Engineering in Difficult Ground Conditions Soft Rocks and Karst, October 2009, in Cavtat, Croatia.  European Regional Symposium EUROCK 2010: Rock

7. ISRM News Journal and Newsletter One hard copy of the News Journal, prepared by the President, was published and distributed by air-mail to all members of the ISRM. This 100 pages issue (Vol. 12, December 2009) contains the annual review of the Society‘s activities in 2009, as well as Technical Articles from the Workshop on Rock Dynamics held in Lausanne. An electronic version of this Volume was posted on the website. Four issues of the Newsletter, prepared by the SecretaryGeneral, were published in 2010 (March, June, September

13


Report of the ISRM Secretary-General for 2010 (cont.) and December). As usual, all members registered on the website, as well as all those who subscribed to it on the website, will receive them by email. The Newsletters are also available for free on the website. ISRM National Groups and individual members are welcome to submit contributions on rock mechanics/rock engineering topics of interest to our technical community.

ceedings published by them, two years after publication. Similar agreements are being negotiated with other publishers of ISRM-sponsored conferences. For several other conferences published by National Groups, the ISRM has already obtained the rights to publish them. More material will be continuously added. The launch of the ISRM digital library took place on 12 October 2010. ISRM members registered on the website are entitled to download the papers for free, up to a certain number per year.

8. ISRM Website The website of the ISRM (www.isrm.net), launched on 1 April 2005, is the main source of information on the ISRM activities and the main channel for communication. Most benefits being offered to the members are available in a password protected members‘ area. Statistics relating to the website usage are summarised in the plot below. 800

10. Educational and Promotional Items As in previous years, the available ISRM educational material has been in demand, and most of it is nowadays accessible from the ISRM website, for free download by ISRM members. The ―Blue Book‖, The Complete ISRM Suggested Methods for Rock Characterisation, Testing and Monitoring: 19742006, launched during the 11th ISRM Congress in July 2007, represented, by far, the majority of the sales in this period.

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Daily Averages

50

Visits Downloads 0 Apr-05

11. ISRM Secretariat The work of the ISRM Secretariat staff includes all the administrative (correspondence, filing, etc.), financial (payments and receipts, accountancy), and secretarial (drafting minutes of meetings, supporting documents, letters) tasks of the ISRM. The Secretary-General, with the help of the Secretariat and the Webmaster, is also responsible for managing the website and, since 2008, for producing and distributing the quarterly electronic Newsletters.

0 Oct-05

Apr-06

Oct-06

Apr-07

Oct-07

Apr-08

Oct-08

Apr-09

Oct-09

Apr-10

Oct-10

12. Support afforded As usual, the Secretariat made ample use, at no charge, of a number of facilities available at the Portuguese National Laboratory for Civil Engineering, LNEC. This included use of office rooms and of other facilities offered to the Secretariat, support for the secretarial and book keeping work, telephone and fax, as well as use of LNEC‘s computer network, namely for internet access and e-mails. This support has long been instrumental to the well-being of the Society and is very much appreciated. The Secretariat also thanks the Portuguese Foundation for Science and Technology, FCT, for the courtesy in providing a grant to the Society.

In offering more services to the rock mechanics community, a series of historical videos was made available to members on the website. These include the Müller lectures delivered by Evert Hoek in 1991 and by Neville Cook in 1995, and the lectures on Geological Engineering by John Franklin. All the keynote lectures of the EUROCK 2009 conference, held in Cavtat, Croatia, are available as videos on the website. It is the intention of the ISRM to have the keynote lectures of its main sponsored conferences available in video format for members in the future. 9. Digital Library The ISRM and the Society of Petroleum Engineers signed a contract for distribution of the papers presented at ISRMsponsored conferences through the OnePetro.org website. OnePetro.org is a multi-society digital library which provides a simple way to search for and access a broad range of technical literature related to the oil and gas exploration and production industry and related subjects. Launched in 2007, OnePetro.org currently contains more than 85,000 documents from 10 organisations, with more being added frequently. In order to enable the inclusion in the digital library of the papers presented at ISRM-sponsored conferences, an agreement was reached with the publisher Taylor and Francis (Balkema now being part of Taylor and Francis) which grants the ISRM the right to include in the digital database all pro-

13. Final remarks The life of the Society and the activity of the Secretariat during the period corresponding to this report were marked by:  launch of the ISRM digital library;  implementation of the modernisation initiatives defined by the Board;  continuation of the increasing trend in the number of individual members of the Society;  increase in the material available to members on the website and in the number of visitors and downloads. Luís M. N. Lamas Lisbon, December 2010

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6th Asian Rock Mechanics Symposium, ARMS6 K. G. Sharma, President of ARMS6 Organising Committee, India (kgsharma@civil.iitd.ernet.in)  Prof. John A. Hudson, Imperial College, UK and President, ISRM, ―Underground Radioactive Waste Disposal: The Rock Mechanics Contribution‖,  Prof. Guowei Ma and Prof. Yingxin Zhou, Singapore, ―Rock Dynamics Research in Singapore: Fundamentals and Practices‖;  Dr. John Read, CSIRO LOP Project, Australia, ―The Large Open Pit Project‖; and  Prof. Herb Wang, University of Wisconsin, USA, ―Deep Underground Instrumentation and Monitoring‖. The Rocha Medal was awarded to Dr. J. Christer Andersson for his PhD thesis on ―Rock Mass Response to Coupled Mechanical Thermal Loading, Äspö Pillar Stability Experiment, Sweden‖. In addition, the following Pre-Symposium Short Courses/ Workshops were also organised on 23 and 24 October 2010:  Two days‘ Workshop on ―Use of TBM/Road Header in Underground Works: Issues and Challenges‖  Short Course on ―Carbon Sequestration in Sedimentary Basins‖  Workshop on ―Rock Mechanics Methods and Tools for Mining Applications‖ An exhibition, having 22 stalls, and exhibiting the products/ services by renowned companies, was organised as a technology showcase to meet the challenges of rock formations in various engineering activities in the field of Water and Energy Resources, Mining, Roads, Underground Works, etc. The following papers were selected for the ARMS Awards.  The ARMS Outstanding Paper Award for Young Scientist and Engineer was awarded to Mr. Tanapol Sriapai from Suranaree University of Technology, Thailand for his paper titled ―Polyaxial Strengths of Maha Sarakham Salt‖. The paper was co-authored with Dr. Kittitep Fuenkajorn, Associate Professor at the Suranaree University of Technology.  The ARMS Outstanding Paper Award was awarded to Dr. (Ms.) Gali Madhavi Latha from the Indian Institute of Science for her paper titled ―Prediction of Stress-Strain Response of Jointed Rocks using Artificial Neural Networks‖. The paper was co-authored with Dr. (Ms.) Arunakumari Garaga, presently Senior Engineer at Nauvata Engineering, Bangalore.

The Indian National Group of the International Society for Rock Mechanics (ISRM) hosted the ISRM International Symposium 2010 and the 6th Asian Rock Mechanics Symposium in New Delhi during 23-27 October 2010, jointly with the Central Board of Irrigation & Power, which houses the Secretariat of the Indian National Group of ISRM (see the cover of this News Journal issue). There was an overwhelming response from the Rock Mechanics Community for the Symposium. More than 150 papers from 27 countries were presented during the Symposium as oral/poster presentations. 275 delegates from 35 countries participated in the Symposium. Sessions on ―Underground and Opencast Mining‖ were also held wherein more than 25 papers from Australia, Canada, China, France, India, Iran, Japan, Singapore, South Korea and USA were presented

Lighting the Lamp of Knowledge at the Opening Ceremony, ARMS6

Keynote Lectures by renowned experts on each day of the Symposium were held so that participants had an opportunity to interact with internationally known personalities in the field of Rock Engineering. The following keynote speakers made these presentations:  Dr. Shinichi Akutagawa, Kobe University, Japan, ―On Site Visualisation as a New Paradigm for Field Measurement in Rock Engineering‖;  Prof. Giovanni Barla, Politechnico di Tornio, Italy, ―Progress in the Understanding of Deep-Seated Landslides from Massive Rock Slope Failure‖;  Prof. Maurice Dusseault, University of Waterloo, Canada, ―Deep Injection Disposal: Environmental and Petroleum Geomechanics‖;  Dr. C. Erichsen, WBI, Germany, ―Challenges in the Design and Construction of Tunnels in Jointed Rock‖;  Prof. Xia-Ting Feng, Institute of Rock and Soil Mechanics, China and ISRM Vice President at Large, ―Application of Intelligent Rock Mechanics Methodology to Rock Engineering‖;  Prof. Yossef H. Hatzor, Ben-Gurion University of Negev, Israel, ―Modelling Dynamic Deformation in Natural Rock Slopes and Underground Openings with Numerical DDA Method‖;

The ARMS Outstanding Paper Award presented to Dr Gali Madhavi Latha by Professor Abdolhadi Ghazvinian

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ISRM Membership: Joining, Benefits and Fees    

How to become an ISRM Member

Access to the ISRM website Members‘ area ISRM Newsletter 1 copy of the ISRM News Journal 1 registration at an advantageous rate as an ISRM member at the ISRM Congress and International and Regional Symposia.  Free download of up to 250 papers/year from the ISRM digital library at OnePetro: www.onepetro.org

Membership of the Society consists of Individual Members within the approved National Groups, Corresponding Members & Corporate Members: For Individual Membership apply for membership of the ISRM through your National Group, this being the recommended type of membership for the development of the Society. However, because some countries do not have a National Group, or due to the preference shown by a candidate for membership directly to the Society through its Secretariat, the category of Corresponding Members was created, the amount of the annual membership fee to be paid, depending on the existence of an approved National Group in the respective country, as stated in the Membership Table of Fees. For Corporate Membership (Companies or Organisations) apply directly to the Secretariat or through your National Groups. For a national organisation to be recognised as an ISRM National Group, it is necessary to formally apply to the President through the Secretary-General for recognition according to the ISRM statutes. This should be an organisation, such as a Society or a Committee that represents Rock Mechanics in that country, either solely concerned with Rock Mechanics, or as part of a broader field of scientific or engineering interest. Each country should have no more than one National Group.

Annual Fees 1. National Groups National Groups shall pay to the Society a basic fee, this amount depending on the number of Members, plus a fixed amount for each Individual and Corporate Member, according to the following scale (in Euros, €). National Group Fee: with 10 individual members or less: €33.00; with more than 10 and less than 40 individual members: €3 x no. of members + € 3; with 40+ individual members: €120.00. Individual Member Fee: €8.00 Corporate Member Fee: €160.00 2. Corresponding Members Corresponding Members shall pay to the Society an annual fee. In order to encourage membership of individuals through the ISRM National Groups, this annual fee is different for Corresponding Members from countries with or without a National Group:  Fee for Corresponding Members from countries without a National Group: €20;  Fee for Corresponding Members from countries with a National Group: €20 in the first year; €40 in the subsequent years.

Benefits for ISRM Members The current benefits for ISRM members are: Individual and Corresponding Members  One copy of the ISRM News Journal  ISRM Newsletter  Members‘ area access in the ISRM website (download of Suggested Methods & Reports, participation in Discussion Forums, etc.)  Ability to download up to 100 papers from the OnePetro website which contains all the papers included in previous ISRM sponsored symposia  Right to participate in the ISRM Commissions and FedIGS Joint Technical Commissions  Registration at an advantageous rate at the ISRM Congress and International and Regional ISRM Symposia  Personal subscription to the International Journal of Rock Mechanics and Mining Sciences at a discounted price  Personal subscription to Rock Mechanics and Rock Engineering at a discounted price. Corporate Members  Listed in the ISRM website, with a link to the Company‘s website  Listed in the ISRM News Journal

Celebrations at the International Symposium ARMS6 held in India

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Organising ISRM Symposia and ISRM Events Organisation of ISRM-sponsored meetings

Organisation of a Congress of the Society

The Society sponsors a co-ordinated programme of National, Regional and International Symposia, and Specialised Conferences. National Groups seeking to host a Regional or International Symposium shall submit a written proposal to the Secretariat, at least one and preferably two to three years before the date of that Symposium. The ISRM International Symposium differs from ISRM Regional Symposia in that it is the selected venue for the annual meetings of the ISRM Council, Board, and Commissions of the Society. National Groups seeking to host a Specialised Conference sponsored by the ISRM shall submit a written proposal to the Secretariat, if possible one year before the date of that Conference, for approval by the Board. ISRM Specialised Conferences are events that may not have the format of a Symposium, are usually of a smaller nature and are focused on a specialised theme. ISRM sponsorship shall be determined by such considerations as technical content, timing in relation to other meetings, cost and benefits to delegates and the organiser‘s experience in running similar meetings. To apply for a Regional or International Symposium or for a Specialised Conference, fill in the appropriate application form available at: http://www.isrm.net/gca/index.php?id=195 All publicity materials and the proceedings themselves are to make reference to ISRM sponsorship, by use of the name and logo of ISRM.

Every four years, the Society holds a Congress on themes of general interest to the majority of the membership. The responsibility for organising a Congress shall belong to the National Group of the country in which the Congress is to be held. National Groups wishing to host a Congress of the Society shall submit a written proposal at the annual meeting of the Council six years before the Congress. Contact the ISRM Secretariat for further details: secretariat.isrm@lnec.pt

ISRM Coming Events (as at publication date) 2nd ISRM International Young Scholars' Symposium on Rock Mechanics 14–16 October 2011, China, Beijing ISRM 12th International Congress on Rock Mechanics 16–21 October 2011, China, Beijing EUROCK 2012 - The 2012 ISRM International Symposium - Rock Engineering and Technology for Sustainable Underground Construction 28–30 May 2012, Sweden, Stockholm EUROCK 2013 - ISRM European Regional Symposium Rock Mechanics for Resources, Energy and Environment 23–26 September 2013, Poland, Wroclaw ISRM 13th International Congress on Rock Mechanics 29 April to 6 May 2015, Canada, Montréal

The ISRM 2007-2011 Board (with guest Antonio Samaniego from Peru)

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Nick Barton Interview (abridged) — the full text of this interInterview recorded by Ivan Vrkljan , Croatia

Nick Barton is the winner of the 2011 Müller Award. The Award was established to honour the memory of Leopold Müller, the founder and 1st President of the ISRM Nick will give the Müller Lecture ―From Empiricism through Theory to Problem Solving in Rock Engineering‖ at 11.00, Tuesday 18 October 2011, during the 12th ISRM Congress in Beijing, China

Nick Barton

Nick Barton was interviewed by Ivan Vrkljan (SecretaryGeneral of the Croatian Geotechnical Society) during his stay in Croatia. Nick went to Zagreb to hold a short course entitled “Rock Engineering for Tunnels (Drill-and-Blast and TBM), Pre-Grouting, Caverns, Dam Abutments, Rock Slopes and Rockfill”. Nick also gave the 10th Nonveiller Lecture entitled: “Pre-Grouting for Water Control and for Rock Mass Property Improvement”. Nonveiller Lectures are organised by the Croatian Geotechnical Society in honour and memory of Professor Ervin Nonveiller. On the occasion of this lecture, CGS awarded the plaque of recognition to Nick in deep appreciation of the scientific and professional support given to the Croatian Geotechnical Society.

quiet-spoken civil engineering and soil mechanics professor Kevin Nash at King‟s College, the late ISSMFE General Secretary in Dr. Bjerrum‟s time as President. Prof. Nash persuaded me to apply to King‟s College and he introduced me to Laurits Bjerrum who was visiting London. Most crucially Nash interested me in a new rock slope stability project at Imperial College, where Peter Cundall of later UDEC/3DEC/FLAC/PFC fame, and John Sharp and David Pentz became my best friends during our Ph.D studies, each one full of enthusiasm about our common rock slope projects. A year later Evert Hoek joined our IC/RSM group next to Hyde Park, and became a valued advisor and professor and research-funds acquirer through RTZ. My subsequent ideal surroundings were in Norway (rock–and-joints are everywhere), where we went as a young family „for one year‟ (this has stretched to 40 years). Research funds from the Norwegian State Power Board (Statkraft) and hydropower projects and challenging questions were in good supply. How to make a good start as a young engineer or scientist? Seek an active university group and one that has a reputation for doing research in a country with challenging projects. Be sufficiently obstinate to follow your beliefs, and question the status-quo...easier 40 years ago...but there are many improvements needed in rock mechanics also today. Some have even occurred in 2011.

Vrkljan: Even before you turned 30, you developed the Q

system that is now used all over the world for the description of rock masses and for the design of support systems for tunnels and large caverns. Even earlier, you defined in your doctoral thesis the empirical criterion for the strength of discontinuities. How is it possible that you have conceived, already in your student days, the ideas that have resulted in methods that are nowadays widely accepted in the international professional community? What message could you pass on to our young colleagues, how to make a good start?

Vrkljan: In your comprehensive monograph from 2006 “Rock Quality, Seismic Velocity, Attenuation and Anisotropy”, you have dedicated a lot of space to geophysical methods. Much is currently expected from

Barton: For sure I have had some fortunate opportunities and fateful parental guidance in teenage and later years, which eventually focused around my much admired and

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view is available on the ISRM website: www.isrm.net geophysical methods as they are fairly inexpensive when compared to traditional testing and investigation methods. They have been proven efficient during rock testing in laboratory and for deep testing during investigation of oil and gas deposits. In this area, Croatian seismologist Andrija Mohorovičić discovered the boundary between the Earth's crust and mantle while analysing the sudden increase in the velocity of waves caused by earthquake, and this phenomenon has been named after him (Moho and Morovičić discontinuity). However, in the sphere of engineering projects, geophysical methods have not fulfilled the expectations of geologists and geotechnical engineers.

Vrkljan: Your Q system and Bieniawski's RMR system have been developed primarily for the tunnelling work and other underground construction. Modifications of these classifications, to enable assessment of slope stability, have also been published (SRM-Romana; QSLOPE). What are the chances that classification systems for estimating slope stability will become as efficient as are the classifications used in tunnelling? Or maybe another approach should be developed? Barton: Classification systems, such as the slightly modified Q-method called Qslope, can be useful for estimating the safe slope angles of unreinforced rock slopes. Substitution of a limit equilibrium or other stability calculation by a classification method, in order to estimate slope-support requirements, seems less likely to be acceptable than it is in the case of tunnels.

How do you think these methods will be developing in the future, and what are the chances that geophysics will achieve in geology and geotechnical engineering the results it is currently achieving in medicine? Barton: I believe that your partly negative opinion about geophysical methods „not as yet fulfilling expectations‟ might be related with the geophysical difficulties in karstic regions, which I believe is an area you have particular experience of in Croatia. I believe that „across the board‟ geophysics has been a great help in hydropower projects (dam foundations, tunnels etc.) around the world, already for 40–50 years (considering refraction seismic and simple cross-hole measurements). The use of cross-hole seismic tomography for the last 25 years has added an additional element of realism. The abilities to link velocity to rock mass quality (and attenuation to deformation modulus) are important in many projects. Some tunnel seismic methods also seem to be of help.

Vrkljan: If we disregard earlier classifications (Terzaghi, Lauffer, Deere et al., Pacher et al.), the following classifications have mostly been used since 1973: Q (Barton), RMR (Bieniawski), and the GSI system (Hoek). The RMi classification (Palmström) is also worth mentioning. Classifications are often used (especially GSI system for those planning to perform standard numerical modelling) for the site rock mass characterisation (rock mass properties determination). After the GeoEng2000 workshop held in Melbourne in 2000, you have had a brief polemic with the discussion leaders (A. Palmström, D. Milne and W. Peck) about the role of water and stress in rock mass characterisation.

Vrkljan: In his keynote lecture given in 1982 at the 23rd US Symposium on Rock Mechanics, Croatian scientist Professor Branko Ladanyi emphasized that one of the main problems in rock mechanics lies in the impossibility to directly measure basic rock mass properties because of the scale factor limitations (scale effects), and time and financing constraints. Although various field and laboratory test methods have been developed in the meantime, these limitations are still present.

Now, ten years later, do you have anything to add about this issue? Barton: My concern remains to actively include stress and water rather than „externalise‟ them when classifying/ characterising. Of more concern to me these days is the absurdity of the algebraic equations linked to GSI (which is only RMR (minus 5?) anyway. I do not believe, nor ever will believe, that one can look at a picture and „classify‟ a rock mass. The children‟s method of diagram recognition is entirely inappropriate to the challenges in describing the anisotropic water-bearing rock masses. It is time to question this widespread method, and the absurdly complex algebraic „links‟ to parameters, that are not actually empirically based. Ivan Vrkljan

What, is your opinion about the role of field and laboratory testing in the definition of mechanical properties of rock masss? Especially in the light of the fact that, regardless of the increase in the scope of testing, it will always be too restricted when compared to the volume of rock mass influenced by geotechnical structures. Barton: Since borehole testing and in situ larger-scale testing in exploratory adits will always, as you say, be restricted in relation to the actual volume of the rock mass influenced by large structures like concrete arch dams, then the interpolating ability of seismic measurements to „span‟ between testing locations and testing results (from boreholes, adits, plate-load tests etc.) advertises itself as a possible means of „averaging‟ or larger-scale measurement.

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2013 Rocha Medal Submissions: Application Deadline

International Society for Rock Mechanics ROCHA MEDAL 2013 Since 1982 a bronze medal and a cash prize have been awarded annually by the ISRM for an outstanding doctoral thesis in rock mechanics or rock engineering, to honour the memory of Past President Manuel Rocha while stimulating young researchers. In addition to the Rocha Medal award to the winning submission, one or two runner-up certificates may also be awarded. An invitation is now extended to the rock mechanics community for nominations for the Rocha Medal 2013. Full details on the Rocha Medal are provided in ISRM By-law No. 7.

Application

Past Recipients 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011

To be considered for an award the candidate must be nominated within two years of the date of the official doctorate degree certification. Nominations shall be by the nominee, or by the nominee's National Group, or by some other person or organization acquainted with the nominee's work. Nominations shall be sent electronically, addressed to the Secretary General, and shall contain:  a one page curriculum vitae;  a written confirmation by the candidate‘s National Group that he/she is a member of the ISRM;  a thesis summary, written in English, with between 5,000 and 10,000 words, detailed enough to convey the full impact of the thesis and accompanied by selected tables and figures;  one copy of the complete thesis and one copy of the doctorate degree certificate;  a letter of copyright release, allowing the ISRM to copy the thesis for purposes of review and selection only;  an undertaking by the nominee to submit an article describing the work, for publication in the ISRM News Journal.

Application Deadline

A.P. Cunha S. Bandis B. Amadei P.M. Dight W. Purrer D. Elsworth S. Gentier B. Fröhlich R.K. Brummer T.H. Kleine A. Ghosh O. Reyes W. S. Akutagawa C. Derek Martin M.P. Board M. Brudy F. Mac Gregor A. Daehnke P. Cosenza D.F. Malan M.S. Diederichs L. M. Andersen G. Grasselli M. Hildyard D. Ask H. Yasuhara Z.Z. Liang G. Li J.C. Andersson D. Park

PORTUGAL GREECE FRANCE AUSTRALIA AUSTRIA UK FRANCE GERMANY SOUTH AFRICA AUSTRALIA INDIA PHILIPPINES JAPAN CANADA USA GERMANY AUSTRALIA SOUTH AFRICA FRANCE SOUTH AFRICA CANADA SOUTH AFRICA ITALY UK SWEDEN JAPAN CHINA CHINA SWEDEN REP. OF KOREA

All relevant information can be obtained from the ISRM website, at http://www.isrm.net.

The nomination must reach the ISRM Secretary General by 31 December 2011.

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Record of the 2nd Annual ISRM Technical & Cultural Field Trip John A Hudson, UK (john.a.hudson@gmail.com)

Participants in the 2010 Technical and Cultural Field Trip to Switzerland

The ISRM Field Trips were inaugurated in 2009, with the visit to the Carrara marble quarries and nearby disused mines, and occur every year except for the Congress years. In 2010, the Field Trip took place in Switzerland on Sunday 13 June and Monday 14 June 2010), i.e., on the two days immediately before the EUROCK2010 meeting which was held at EPFL in Lausanne. Dr Christophe Bonnard led the Field Trip with its 16 participants representing 11 nationalities. A wide variety of technical and cultural visits was packed into the two days, including a visit to Lausanne Cathedral, landslide locations and castles. The technical highlight was a comprehensive visit to and explanation of the La Frasse landslide. The cultural highlight was a detailed explanation of the Etivaz cheese maturation process which included a visit to the ‗cheese cave‘, see photo Christophe explaining opposite.

Beautiful Swiss landscape in the clouds

Inspecting the maturing cheeses

a technical point

12th century Chillon castle, on the Lake Geneva shore,

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2010 Activity Report by the ISRM Vice-President for Africa Francois Malan, S. Africa (Francois.malan@groundwork.co.za) 1. Introduction This report summarises the ISRM activities for the Africa region for the period of September 2010 to March 2011. During this period, the South African National Group (SANIRE) remained the only active group on the continent, Ghana not having paid their fees for over three years. SANIRE has now adopted the policy that all geotechnical engineers from other African countries are welcome to join SANIRE.

90

85.42

80 70

Percentage

60 50 40 30 20 8.33

10

2. Conferences and symposia The tradition of holding an annual SANIRE symposium was maintained in 2010 as a local symposium was held on 14 October 2010 in Carletonville. An interesting seminar that is planned for April 2011 in Johannesburg by the SAIMM is titled ―Centenary of Rockburst Research‖. In 1908, the Ophirton Earth Tremors committee was commissioned to investigate earth tremors originating in the Witwatersrand Gold Mines in Johannesburg. Subsequent rockburst research over the years in the deep level mines in South Africa propelled South Africa into the fore in research into this phenomenon. A further geotechnical conference planned in South Africa is the Young Geotechnical Engineers Conference, 2011. This Conference will be held in the Kruger National Park.

1.04

1.56

2.08

1.3

0.26

Canada

United States

Africa

United Kingdom

Brazil

0 South Africa

Australia

Country

Countries in which SANIRE members reside.

are still active in South Africa. Surprisingly, the numbers of members active in the rest of Africa is low and it is planned to increase this in future. 4. SANIRE website The SANIRE website (below) has become an important and frequently used communication tool during 2010. The success of this site can be attributed to the efforts of the webmaster (Mr. Geoffrey Potgieter).

3. Current status of SANIRE Growing numbers of rock engineers from diverse backgrounds are joining SANIRE. The membership has reached a record total for the 2010 financial year and currently stands at 406 (which includes all categories of membership. SANIRE has added 98 new members in the past 11 months. Associate membership has grown by far the most, as has been the case for the past two years, see below. As discussed in the previous report, it appears as if the trend of emigration of skilled rock engineering personnel to other continents has now been reversed and a number of rock engineers have recently returned to the country. The Figure at the top of the next column illustrates the distribution of SANIRE by country, showing that 85% of members

The SANIRE website: www.sanire.co.za

250 Honorary Life Fellows Fellows Members Associate Members

200

227

Members

154

150

146

147

139

138

120 110

143 138

111

137 124

110

100

147

153

110

90 75 75

50

36

36

14

14

37

32

35

36

34 22

0 2001

2002

12

2003

12

2004

12

12

2005

2006

12

2007

12

2008

22 12

2009

22 13

2010

Year

SANIRE membership per year according to category

Statistics of the usage of the SANIRE website

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2010 Activity Report by the ISRM Vice-President for Asia Abdolhadi Ghazvinian, Iran (abdolhadi@yahoo.com) 1.2. India There has been a dramatic increase in the membership of the India National Group which is now represented by more than 452 individual members and has been very active in organising various activities. A brief glance at its activities during the reporting period is summarised below:  Organised a Seminar on Rock Engineering, on 8–9 March, 2010 in New Delhi;  Organised a Seminar on Meeting Rock Mechanics Challenge of Deep Underground Mining on 22–24 April, 2010;  Organised a Workshop on ―Applications of Rock Mechanics—Tools and Techniques‖, on 15–17, January 2010, Nagpur (Maharashtra); and  Indian National Group Rock Mechanics Symposium on ―Advances In Rock Engineering‖, 23–27 October, 2010, New Delhi.

Asia has begun a new era in rock mechanics because of its extensive and wide application in civil, mining and petroleum engineering projects. The region is rapidly emerging and advancing towards the construction of complicated projects. This requires the application of modern and new principles of rock mechanics for the successful implementation of such projects, and to overcome the environmental requirement challenges. Also, the election of Prof. Xia-Ting Feng as the next President of the ISRM has boosted the morale of Asian researchers and encouraged them to move forward and exploit every possibility in this important field. This may be viewed as a sign of the recognition of the tremendous rock mechanics activities in Asia. The ISRM membership in Asia is increasing and this is due the scope and importance of the region. Apart from Thailand, we have witnessed Indonesia emerging as an active group during this time. A concise report of activities by the ISRM National Groups in Asia from May, 2009 to October, 2010 is given below.

ISRM International Symposium 2010 and ARMS6 The Indian National Group is very busy and active in organising a big event, i.e., the ISRM International Symposium 2010 and 6th Asian Rock Mechanics Symposium (ARMS 2010) taking place in the month of October, 2010 in New Delhi. A separate website for the event with the domain name www.arms2010.org is available for further information. The 13th Congress of International Society for Rock Mechanics (ISRM) is proposed to be held in Agra in November, 2015 [Ed: Montreal turned out to be the elected city for the 13th Congress]. A Special Publication manual on Rock Mechanics will be circulated at the upcoming International Symposium and 6ARMS Symposium 2010.

1. ACTIVITIES OF ISRM NATIONAL AND REGIONAL GROUPS IN ASIA 1.1. China The China National Group is represented by the Chinese Society for Rock Mechanics and Engineering (CSRME) which currently has 554 individual members and 14 corporate members. The activities during the specified period are summarised as below:  SINOROCK2009: ISRM Sponsored International Symposium was held in Hong Kong on 19–22 May, 2009;  Organised 12th ACUUS Conference (ACUUS2009), 1819 Nov, 2009, Shenzhen, China, Using the Underground of Cities: for a Harmonious and Sustainable Urban Environment;  Organised the 7th International Symposium on Rockbursts and Seismicity in Mines, 21–23 August, 2009, Dalian, China;  ISRM NG-China celebrated its 30th Anniversary in August 2009;  3rd International Conference on New Developments in Rock Mechanics and Engineering & Sanya Forum for the Planning of City and City Construction, 24–26 May, 2009, Sanya, China;  CSRME hosted the 7th Session of the Annual Meeting of the Chinese Association of Science and Technology (CAST), 8–10 Sept., 2009, Chongqing, China;  National Workshop on the Safety of the Deep Tunnels at the Jinping Hydropower Station, China. 6–9 Nov., 2009;  8th Cross-Strait Tunnel and Underground Engineering Conference was held on 18–19 Nov., 2009 in Taipei.  9th Cross-Strait Tunnel and Underground Engineering Conference was held on 18–19 August, 2010 in Luoyang, China;  Preparation is in progress for the ISRM 2011 Congress;  There have been extensive programmes on Exchange and Co-operation.

1.3. Iran The Iran National Group represented by the Iranian Society for Rock Mechanics (IRSRM) has organised various activities.  Launched the Iranian Society for Rock Mechanics website: www.irsrm.net  Organising the 4th Iranian Rock Mechanics Conference in May 2011.  Organising a One Day workshop on ―Instrumentation in Geo-mechanics Engineering Projects‖ to be held in November, 2010.  Organising a One Day workshop on ―Lidar Scanning‖ to be held in December, 2010 to January, 2011.  Published a magazine in the English and Persian languages to distribute to all existing members. 1.4. Israel The Israel National Group is represented by the Israel Rock Mechanics Association (IRMA). The activities during the reporting period have not been reported at the time of going to press. 1.5. Japan The Japanese Committee for Rock Mechanics (JCRM) with

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2010 Activity Report by ISRM Vice-President for Asia (cont)  Organised a successful Workshop, Norwegian Tunnelling Technology on 17–18 Feb., 2009, in Singapore.  Two Seminars on ACI Nozzleman Certification took place on 6 Oct., 2009 in Singapore.  A two-day short course on ‗Geological Investigations and Ground Characterisation for Tunnelling and Cavern Construction was held on 11–13 November, 2009, in Singapore.  The International Conference on Discontinuous Deformation Analysis 2009, was held on 25–27 Nov., 2009, in Singapore.  The SRMEG is to host the 13th International Conference of the Associated Research Centres for Urban Underground Space (ACUUS) in 2012 in Singapore.  SRMEG is the co-organiser of the 12th ISRM Congress with the China NG to be held in Beijing in October, 2011.  Organised a three-day short course on Discontinuum Modelling in Rock Mechanics with UDEC Applications, on 30 Aug. to 1 Sept. 2010.  Organised a NATM Workshop on 11–12 November 2010, in Singapore.  Conducted monthly EAS-SRMEG Seminars in July, Aug. & Sept., 2009.

its 370 ISRM individual members and 44 corporate members has organised various activities during the reporting period.  Made several important publications on rock mechanics and rock engineering, especially the publication of the international Journal JCRM Vols. 5 & 6 and Newsletters Nos. 91–95) for Japanese members.  Rock Net mail (No. 240-298) and A CD-ROM titled ‗Rock Mechanics 08‘ has been composed and distributed to Japanese Members.  The JCRM Awards for 2009 have been announced. 1.6. Korea The Korea National Group is represented by the Korean Society for Rock Mechanics (KSRM). The Korea NG has been very active and has organised various activities, as are summarised below.  Organised two national conferences, one in Oct, 2009, and another in May, 2010.  Special issue: KSRM published six issues of the Journal of Korean Society for Rock Mechanics, and a bi-monthly ‗webzine‘ named ‗U-Space‘ since March, 2009.  The (KRMC2010) Korean Rock Mechanics Conference is also going to be held in Seoul, simultaneously, with the ISRM & 6th ARM Symposium New Delhi.  Organised the autumn conference in 2009 in conjunction with the ―Korea-Japan Joint Symposium on Rock Engineering‖.  Made several important publications on rock mechanics and rock engineering, especially publication in two languages.  Supporting and being involved in the organisation of the 12th ISRM Congress.

1.11 Southeast Asia Thailand The Thai National Group represented by Thai Rock Mechanics has been active:  The Second Thailand Symposium on Rock Mechanics (Thai Rock 2009) represents a continuing mission of the Thai leading academic institutions to promote the significance and development of rock mechanics knowledge and profession in Thailand and neighbouring countries.  A one-day short course on 3D Lidar Scanner for Rock Mass Classification preceded the conference and was presented by Prof. John M. Kemeny.

1.7 Middle East Region The Middle East Regional Group is represented by the Middle East Society for Rock Mechanics, based in Abu Dhabi, United Arab Emirates. This regional group became affiliated to the ISRM last year. The activities during the reporting period have not been reported.

2 OUTLOOK IN ASIA The upward trend of expansion and progress in the activities of the Asian National Groups can be perceived because the ongoing/incoming years are witnessing various international events in Asia, especially in Iran, China, India, Korea, Japan and Singapore. In addition, there are many national and local conferences and symposiums planned by the National Groups and Commissions. Efforts to establish ISRM National Groups in other parts of Asia, including the Philippines, west and middle Asia, is our future strategy.

1.8 Indonesia The Indonesian Group has:  Organised one geotechnical assessment course, and  Will be organising a National Geotechnical Workshop in October, 2010. 1.9 Nepal The Nepal National Group is represented by the Nepal Geotechnical Society. The activities during the reporting period have not yet been reported. 1.10 Singapore The Singapore National Group, represented by the Singapore Society of Rock Mechanics and Engineering Geology (SRMGE), has increased its membership to 85. and has been active in organising various activities, a summary of which follow.

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2010 Activity Report by ISRM Vice-President for Australasia Tony Meyers, Australia (tony@rocktest.com.au) 2010 MEMBERSHIP

Australia

257

New Zealand

100

Total

357

ROCK MECHANICS EVENTS HELD BY ISRM RELATED GROUPS The following rock mechanics related events were organised in 2010 and early 2011 by local chapters of the Australian Geomechanics Society and the New Zealand Geotechnical Society. Topic

Presenter

Date

Location

Deep Fault Drilling Project – Alpine Fault

Tim Davies

18 Feb 2010

Wellington NZ

A Case Study of Abandoned Mine Subsidence at Dominion, Nova Scotia, Canada,

David Forrester

4 March 2010

Newcastle NSW

Landslide Risk Management and Ground Characterisation on the Sugarloaf Pipeline Project

Jeremy Barber

24 March 2010

Melbourne Vic

The Failure of Analcóllar Dam

Professor Gens

10 May 2010

Auckland NZ

A Practical Guide to Abandoned Mine Subsidence Assessment and Mitigation

David Nott

12 May 2010

Sydney NSW

Ground Anchor Design and Construction

Iain Haycock

17 Jun 2010

Christchurch NZ

Design, Excavation and Performance of Rock Cuttings on the Karratha to Tom Price Road

John McDermott

13 July 2010

Perth WA

Lessons Learned from Landslides

Scott Burns

26 Aug 2010

Christchurch NZ

Geotechnical issues in mechanised tunnelling

Paul Marinos

9 Sept 2010

Brisbane Qld

Rock Mass Characterisation

Paul Marinos

14 Sept 2010

Perth WA

The National Seismic Hazard Model

Mark Stirling

28 Sep 2010

Christchurch NZ

The influence of Water on Slope Instability

Laurie Wesley

14 Oct 2010

Bay of Plenty NZ

Earthquake Experiences in Christchurch

David Dobbie

23 Nov 2010

Auckland NZ

Darfield Earthquake Recovery

S van Ballegooy

30 Nov 2010

Wellington NZ

Closely Jointed Rock Masses Talk

Stuart Read

3 Feb 2011

Wellington NZ

The Art of Tailings Engineering

Alistair Cadden

14 Sep 2011

Perth WA

―It‘s Our Fault‖

Russ Van Dissen

10 Aug 2010

Wellington NZ

Seismic Engineering Management

Various

13 Oct 2010

Sydney NSW

Geotechnical Risk

Various

14 Oct 2010

Sydney NSW

Copper Mining in Chile

Luis Rojas

8 Nov 2010

Newcastle NSW

Through the Eyes of a Miner

Joseph Divis

8 Nov 2010

Wellington NZ

Developing Underground Space

Fiona Chow

8 Feb 2011

Perth WA

Ground Anchors

Devon Mothersville

9 Feb 2011

Melbourne Vic

Each of these 2 hour events attracted between 20–160 geotechnical practitioners. Most events were provided to attendees at no cost.

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2010 Activity Report by ISRM V-P for Australasia (cont) ROCK MECHANICS EVENTS HELD BY NON-ISRM RELATED GROUPS Workshop Topic

Date

Location

Provider

Caving

22 April 2010

Perth, WA

ACG

Application of various ground control techniques to specific mining methods

20 May 2010

Brisbane Qld

EAGCG

7th Large open pit mining conference

27 July 2010

Perth, WA

AusIMM

Open pit rock mass modelling seminar

29 July 2010

Perth, WA

ACG

Planning for sustainable mine closure

18 Aug 2010

Brisbane, Qld

JKTech

Ground support for underground and open pit mining

24 Aug 2010

Perth, WA

ACG

Ground support in mining (basic)

25 Aug 2010

Perth, WA

ACG

Ground control management plans

15 Oct 2010

Adelaide

EAGCG

2nd Australian ground control in mining conference

23 Nov 2010

Sydney NSW

UniNSW

14 Tunnelling conference

11 Mar 2011

Auckland NZ

ATS

Shotcrete quality assurance

20 Mar 2011

Canberra

ACG

Leading edge technology for surface and underground ground control

5 May 2011

Newcastle NSW

EAGCG

Advanced application of seismology in mines

10–13 May 2011

Perth WA

ACG

Dynamic rock support workshop

19–20 May 2011

Perth WA

ACG

Ground support in open pit mines

17 May 2011

Perth WA

ACG

th

ACG - Australian Centre for Geomechanics EAGCG - East Australian Ground Control Group IESE - Institute of Earth Sciences and Engineering ATS – Australian Tunnelling Society Each of these events attracted approximately 50–150 rock mechanics practitioners. The average registration fee for these events was between €175 and €570. No discounts were provided to ISRM members. OTHER ISSUES The Regional VP communicated regularly with ISRM Members via the ―ISRM RockNotes‖ feature which appeared in quarterly issues of Australian Geomechanics Journal and New Zealand Geomechanics News. On February 22, the first of 589 earthquakes to date, (March 13, 2011), struck Christchurch NZ. The first quake of magnitude 2.3 occurred at 01:07 at a depth of 2km below the city. Subsequent quakes occurred at depths ranging from 2 km to 15 km. The quake having the maximum magnitude of 6.3 struck at 12:51 at a depth of 5 km. Aftershocks up to magnitude 4.3 are still occurring to date. Currently the number of confirmed dead is 166, although authorities expect the number to exceed 180. Damage to infrastructure is estimated to exceed NZ$15 billion. The quake triggered massive rockfalls and landslides. The National Mine Safety Framework (NMSF) is in the process of being established by the Ministerial Council on Mineral and Petroleum Resources. It aims to achieve a nationally consistent occupational health and safety regime for

the Australian mining industry. The NMSF is made up of the seven strategies below.  Nationally consistent legislation  Competency support  Compliance support  A nationally co-ordinated protocol on enforcement  Consistent and reliable data collection and analysis  Effective consultation mechanisms  A collaborative approach to research This development has implications for mining rock mechanics practitioners, especially those working for companies that have sites in different States. The Australasian mining industry is currently active with strong demand for mineral resources, particularly from Asia. This activity has created employment opportunities for rock mechanics practitioners for several years and the demand is expected to continue. A record $251 billion from commodity exports will be brought in to Australia in the 2011-12 financial year after reaching $186 billion in 2010-11. The mining boom is expected to continue until at least 2015-16.

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2010 Activity Report by ISRM Vice-President for Europe Nuno Grossmann, Portugal (grossmann@lnec.pt) In 2010, the following three ISRM-Sponsored events took place in Europe: The 3rd International Workshop on Rock Mechanics and Geo-Engineering in Volcanic Environments, the first ISRM-Sponsored Specialised Meeting, organised by the Sociedad Española de Mecánica de Rocas (the ISRM NG, Spain), and held in Puerto de la Cruz (Canary Islands), Spain, on 31 May – 1 June 2010, in conjunction with the International Congress ―Cities on Volcanoes 6, Tenerife 2010‖; this Workshop was a great success, having attracted around 120 participants. The technical component included one keynote lecture and the oral presentation of around 50 papers. The proceedings have been produced as a hard copy volume, entitled ―Volcanic Rock Mechanics‖, having more than 350 pages. The technical visits allowed the participants agreeable get-togethers, and gave them the opportunity to enjoy the beauties of the Canary Islands. The 2nd Annual ISRM Technical and Cultural Field Trip, visiting landslides in the Vaud and Freiburg Cantons, in Switzerland, on 13–14 June 2010 with 18 participants, see page 21. EUROCK 2010, the European ISRM-Sponsored Regional Symposium 2010, on Rock Mechanics in Civil and Environmental Engineering, organised by the Swiss Society for Soil and Rock Mechanics (the ISRM NG, Switzerland), and held in Lausanne, Switzerland, on 15–18 June 2010. This Symposium was also a great success, having gathered around 340 participants. The technical part included five keynote lectures and the oral presentation of around 200 papers, in parallel sessions, as well as an open discussion on the future of Rock Mechanics in Europe; the proceedings have been produced, both as a hard copy volume with more than 850 pages, and as a CD. The EUROCK Award for the Best Paper by a Young Scientist/Engineer was also given at EUROCK2010 with 33 young authors participating in the competition. The winner was Azania Mufundirwa of Japan, and the runner-up was Matt J. Lato of Canada. The social programme enabled the participants to get together, and the technical visit, on the last day, took them to the Valais Canton. Besides these meetings, several European ISRM National Groups have organised national meetings, many of them with international participation, amongst which, as is tradition, was the Geomechanics Colloquy, in Salzburg, Austria. The European Council Meeting 2010 took place in conjunction with the EUROCK2010 Symposium, and, among other issues, the Council members were informed that the European ISRM-Sponsored Regional Symposium 2012 (EUROCK2012) would take place in Stockholm, Sweden, and that the complete candidatures for the European ISRMSponsored Regional Symposium 2013 (EUROCK2013)

EPFL campus, venue of the EUROCK2010 Symposium

would have to be received at the ISRM Secretariat, in Lisbon, in time to be submitted to the ISRM Board meeting in New Delhi, India, (2010 October). They were also informed that the former EUROCK Steering Committee, which includes the past European Board members, had comprised the Award Committee for the EUROCK 2010 Best Paper by a Young Scientist/Engineer. The European Council Meeting 2011 will take place in conjunction with the 12th ISRM International Congress on Rock Mechanics, in Beijing, China (2011 October). At their 2010 meetings, in New Delhi, India, the ISRM Board selected as the European ISRM-Sponsored Regional Symposium 2013 (EUROCK2013), a Symposium on Rock Mechanics for Resources, Energy, and Environment, to be held in Wroclaw, Poland, on 23–26 September 2013. The ISRM Council decided to hold the 2012 ISRM meetings in conjunction with EUROCK 2012, the ISRM-Sponsored International Symposium 2012, on Rock Engineering and Technology for Sustainable Underground Construction, to be held in Stockholm, Sweden, on 28–30 May 2012. The complete candidatures for the European ISRMSponsored Regional Symposium 2014 (EUROCK 2014) have to be received at the ISRM Secretariat, in Lisbon, in time to be submitted to the ISRM Board meeting in October in Beijing, China.

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2010 Activity Report by ISRM Vice-President for N. America Derek Martin, Canada (derek.martin@ualberta.ca) United States The American Rock Mechanics Association (ARMA, www.armarocks.org) continues to help shape and respond to issues of national interest and concern including carbon sequestration, energy resource production, civil engineering infrastructure, and research and development through the proposed Deep Underground Science and Engineering Laboratory (DUSEL). These opportunities were discussed at the 44th US Rock Mechanics Symposium in Salt Lake City Utah, in June 2010. A record 444 persons from 23 countries attended the event, presenting close to 300 oral and poster presentations. The symposium featured 20 invited speakers including Dick Robbins who delivered the MTS Invited Lecture. A special workshop on Geomechanics preceded the symposium and was attended by 80 people.

Canada The Canadian Rock Mechanics Association (CARMA http://www.carma-rocks.ca/) serves as the ISRM‘s National Group for Canada. Members are from CARMA‘s two constituent groups: the Rock Mechanics Division of the Canadian Geotechnical Society (CGS); and the Society for Rock Engineering of the Canadian Institute of Mining and Metallurgy (CIM). A combined total of 250 CIM and CGS members paid for ISRM membership in 2010. The 2009–2010 CARMA Executive consists of: the Chair, Chris Hawkes, University of Saskatchewan; Erik Eberhardt, University of British Columbia; Jamie Archibald, Queen's University; Luc Beauchamp, Mines and Aggregates Safety and Health Association, Ontario; and the Secretary/ Treasurer, Giovanni Grasselli, University of Toronto. The Canadian Rock Mechanics Association (CARMA) will be hosting the 13th ISRM Rock Mechanics Congress in 2015 in Montreal, Canada. This Congress, will be chaired by Dr. Ferri Hassani of McGill University and has the support of ARMA, the Canadian industry, the Canadian Institute of Mining, Metallurgy and Petroleum (CIM), the Federal Government of Canada, the Provincial Government of Quebec, and of academia from across Canada. Slope Stability 2011, the International Symposium on Rock Slope Stability in Open Pit Mining and Civil Engineering will be held on 18–21 September 2011 in Vancouver, Canada, www.slopestability2011.ca . The Canadian Geotechnical Society and the International Society for Soil Mechanics and Geotechnical Engineering, invite you to the 14th Pan-American Conference on Soil Mechanics and Geotechnical Engineering (PCSMGE), the 64th Canadian Geotechnical Conference (CGC) and the 5th Pan-American Conference on Teaching and Learning of Geotechnical Engineering (PCTLGE) at the Sheraton Centre Hotel in Toronto, Ontario, Canada from October 2–6, 2011.

ARMA Fellows

John A. Hudson and Wolfgang Wawersik were inducted into the ARMA Fellows at the Salt Lake City symposium. The ARMA Fellows program recognises individuals who have achieved outstanding accomplishments in the area of rock mechanics and who have contributed to the professional community through ARMA. John and Wolfgang receive their ARMA Fellows medals at the 44th US Rock Mechanics Symposium in Salt Lake City in June, 2010. Awards

Awards

The 2010 ARMA Awards were also given out at the Salt Lake City symposium. Recipients were as follows. 2010 Award for Research in Rock Mechanics: Russ Detwiler, ―Measuring Coupled Geochemical Alteration and Geomechanical Deformation in Discrete Variable-Aperture Fractures‖, presented at the 42nd US Rock Mechanics Symposium, San Francisco, June 2008. 2010 Award for Applied Rock Mechanics Research: Takatoshi Ito, ―A New Strategy of Hydrofracturing for Deep Stress Measurements, BABHY, and its Application to a Field Test‖, Presented at the 42nd US Rock Mechanics Symposium, San Francisco, June 2008. 2010 Dr. N.G.W. Cook Dissertation Award: Joshua Taron, ―Geophysical and Geochemical Analyses of Flow and Deformation in Fractured Rock‖, The Pennsylvania State University, December 2009. 2010 Case History Award: Jonny Rutqvist, Barry Freifeld, Yvonne W. Tsang, Ki-Bok Min, Derek Elsworth, ―Coupled Analysis of Change in Fracture Permeability during the Cooling Phase of the Yucca Mountain Drift Scale Test‖, presented at the 42nd US Rock Mechanics Symposium, San Francisco, June 2008.

Douglas Stead (Simon Fraser University, Burnaby, BC) was awarded the Canadian Geotechnical Society‘s 2009 Franklin Award for contributions made in the fields of rock mechanics and rock engineering. Projects

During 2009-10 the Centre for Excellence in Mining Innovation (CEMI), located in Sudbury, Ontario, has hosted a series of Experimental Design Workshops for its proposed International Fault Slip Control Research Initiative (IFSCRI). More information can be collected from the CEMI website: http://www.miningexcellence.ca/projects/ifscri/ On 9 February 2011, CEMI hosted public seminars on Rockmass Characterisation. Those videos can be viewed at www.miningexcellence.ca/ On 25 November 2010, Rio Tinto announced the establishment of the Rio Tinto Centre for Underground Mine Construction (RTC-UMC) at the Centre for Excellence in Mining Innovation (CEMI) located in Sudbury, Ontario, Canada. Rio Tinto will be investing $10 million dollars over five years to undertake research at the centre. Dr. Peter K. Kaiser is the President/CEO of CEMI.

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2010 Activity Report by ISRM Vice-President for S. America Álvaro J. González-García, Colombia (ajgon@cable.net.co) ISRM Activity Report for South America Rock mechanics development in the region was in the beginning mainly associated with mining, railway, dam and roadway engineering. Due to significant reserves of gas and oil in some of the countries in the region, such as Venezuela, Brazil, Ecuador, Bolivia and Colombia, rock mechanics activities as related to oil engineering have shown an increase in recent years.

This event was preceded by a Workshop on Natural Disasters (17 August), the IV Brazilian Young Geotechnical Seminar (18 August) and the V Luso-Brazilian Geotechnical Congress (19 August). There were more than 1,200 participants and it included the V Brazilian Symposium on Rock Mechanics on 21 August. Among the main Lecturers were Dr. Harry Poulos (De Mello Lecture), introduced by Prof. John Burland and in the Rock Mechanics Symposium: Brazilian Engs. Arsenio Negro, Milton Assis Kanji, Luiz Jacques de Moraes, and from Austria, Eng. Wulf Schubert. The ISRM VP for South America attended this large event by invitation of the Brazilian Geotechnical Society. Chile The Chilean Catholic University organised the 5th International Seminar on Deep and High Stress Mining, DEEPMINING 2010, from 6–8 October, 2010, preceded by courses on: Ground Control in Highly Stressed Hard Rock Mines (P.K. Kaiser, M. Cai); Destress Blasting/Rock Preconditioning using Explosives (P. Andrieux); and on MicroSeismicity Monitoring (R. Lynch). Colombia The Colombian NG (SCG), together with the National University of Colombia, organized the XIII Colombian Geotechnical Congress and the VII Colombian Geotechnical Seminar, this last one dedicated to Mining Geotechnics, from 21–25 September, 2010, in the city of Manizales, located in the centre of the Colombian Coffee Belt. The main lecturers for the Mining Seminar were Antonio Samaniego (Peru), Gianfranco Perri (Venezuela), Tarsicio Celestino (Brazil) and Alvaro Correa (Colombia) — and for the Congress, Laurence Wesley (New Zealand), Daniel Salcedo (Venezuela), Tarsicio Celestino (Brazil), Jaime Suarez (Colombia) and Juan Montero (Colombia). About 300 people attended the events, which, besides the main lectures, had 77 papers, a technical exhibition and a technical tour to several works located nearby Manizales. Costa Rica The Costa Rican Geotechnical Association, the ISRM NG, organises periodic local lectures and meetings on Rock Mechanics. Paraguay The Paraguayan NG (Sociedad Paraguaya de Geotecnia-SPG), which has a Rock Mechanics VicePresidency, continued the Lecture Series on the Weak Rocks and Indurated Soils of Paraguay. Peru The Peruvian NG (Sociedad Peruana de Geoingeniería -SPDG), in association with the Peru Mining Engineering Institute (IIMP), organised the VII South American Rock Mechanics Congress, held from 2–4 December 2010 in the Sheraton Hotel, Lima, as a Regional ISRM event. The main lecturers were Prof. Evert Hoek (Canada), Prof. John A Hudson (UK, ISRM President), Prof. Xia-Ting Feng (China, ISRM President-Elect), Nick Barton (UK & Brazil), Carlos Carranza-Torres (Argentina & USA), Tarsicio Celestino (Brazil), David Wood (Canada) and Rimas Palkanis (Canada). There were also the oral presentations of 38 papers, mainly from Peru and South America, but also from outside the region. The event was preceded by three short courses: Use of RocScience Codes in the Design and Analyses of Excavations in Rock (Carlos Carranza-Torres); Rock Engineering in Tunnel Excavation with Conventional and TBM Methods (Nick Barton); and Empirical Design Methods in Underground Mining (Rimas Palkanis). A post-event

1. ISRM National Groups and Members At present (December, 2010) the South American Region has 9 National Groups, with two new groups from Costa Rica and Bolivia, more than 160 ordinary members and 1 corporate member (Petrobras from Brazil). Of the National Groups, only Chile, Peru and Bolivia do not have a website. The National Group membership is Argentina 7, Bolivia 27, Brazil 54, Chile 14, Colombia 20, Costa Rica 10, Paraguay 6, Peru 12, Venezuela 11. The total for S. America is 161. The Vice-Presidency has advanced communication with Ecuador to form an ISRM group and also intends to get in touch with Panama and Mexico. 2. NG Activities Argentina The Argentinian Society of Geotechnical Engineering (SAIG) held CAMSIG-2010, the 20th Argentinian Congress on Soil Mechanics and Geotechnical Engineering from 6–9 October, 2010, in Mendoza. This meeting included sessions on Rock Mechanics, Mining Engineering, Seismic Engineering and Geology and Geotechnics and the main lecturers were Carlos Costa (Argentina), Carlos Santamarina (Argentina-USA), I. Ortuño (Spain), Pedro Ortigosa (Chile) and Oscar Vardé (Argentina). Brazil In Brazil, several geotechnical events were held or are programmed by ABMS (NG-Brazil). Of these the most important is COBRAMSEG 2010, the 15th Brazilian Congress on Soil Mechanics and Geotechnical Engineering, which took place from 20–22 of August, 2010 in Gramado, Rio Grande do Sul.

Dr Harry Poulos giving the De Mello Lecture

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2010 Activity Report by ISRM V-P for S. America (cont)

VII CSMR- Opening Session: Feng, Hoek, Soldi, (IIMP), Carrizales (IIMP), Hudson, González

3-day technical tour was organized to the Cerro Verde Mining Field near Arequipa. There was also a technical exhibition with around 20 stands. More than 450 people attended the Congress. One day before the event, the South American ISRM Council met with the attendance of 8 of the 9 countries (the Venezuelan delegation had travel difficulties). Dr. Antonio Samaniego from Perú was elected as a candidate for the next S. American ISRM Vice-Presidency.

ture), Jaime Graterol, Roberto Centeno, Daniel Salcedo and Pietro De Marco. 3. General Comments Most ISRM NG groups in South America are merged with the National Geotechnical Societies and only Brazil has a Rock Mechanics Committee (as well as a Tunnelling Committee) and Paraguay a Rock Mechanics Vice-Presidency. From the economic viewpoint, this merging is a worldwide, common, and somewhat desirable feature for small National Groups, and does not allow the easy separation of rock mechanics activities from general geotechnical activities. Independent NG groups had been recently created in Chile, Perú and a new one was organised in Bolivia: all three countries have an intense mining industry, and these newly formed groups consist mainly of the mining professions.

ArSPDG President: Dr. A. Samaniego

gentina was selected to organise the VIII South American Rock Mechanics Congress in 2015 and Costa Rica was desginated to hold the II South American Rock Mechanics Seminar in 2012. Venezuela The Venezuelan NG (SVG) held the 19th Venezuelan Geotechnical Seminar, from 28–30 October, 2010 in Caracas, which included some papers on rock mechanics. The main lecturers were Venezuelan Engs. Nelson Rodriguez (Perez Guerra Lecture), Ivan Contreras (Lupini Lec-

ISRM Vice-President: Prof. A. J. González

30


Introduction to the ISRM Commissions John A Hudson, UK, ISRM President (john.a.hudson@gmail.com) produce reports and guidelines  Commission on Rock Engineering Design Methodology President: Feng Xia-Ting (China) Purpose: To produce a report on modern rock engineering design with an auditing capability  Commission on Rock Spalling President: Mark Diederichs (Canada) Purpose: To bring together the disparate information on rock spalling and produce an associated report  Commission on Testing Methods President: Resat Ulusay (Turkey) Purpose: To prepare the ISRM Suggested Methods

The operational period of each ISRM Commission is for the duration of each Presidential tenure and so, for the Commissions currently active, this is the period 2007–2011. These Commissions will provide the products of their work at the 12th ISRM Congress being held in Beijing in October 2011. The Commission reports in the following pages therefore represent notes on their work leading up to the completion of their products on or before the ISRM Beijing Congress. One or more of the Commissions, e.g., the Testing Methods Commission will continue into the next Presidential period, 2011–2015 where the work is either on-going or requires more than one four-year period. These Commissions are a crucial component of the ISRM‘s operation because they enable new developments to be made and, through the publications of the Commissions‘ reports, for the information to be disseminated to the ISRM members and the wider public. Each Commission is organised with a Commission President who is supported by Commission members, typically 5 to 10 such members, and has a task concentrating on a specific research objective or collation of information about a particular subject. This means that each of the Commissions must have a conscientious Commission President and be well structured with appropriate milestones, so that the Commission will definitely produce a worthwhile product at the end of its lifetime. There is no value in establishing ISRM Commissions if they do not produce anything worthwhile. Accordingly, and when establishing the Commissions at the beginning of my 2007-2011 tenure, I asked all the current Commission Presidents to set out their objectives and milestones (and associated yearly presentations), and to promise me that they will do their best to achieve the objectives. Currently, there are nine ISRM Commissions as follows (in alphabetical order):  Commission on the Application of Geophysics to Rock Engineering President: Toshifumi Matsuoka (Japan) Purpose: To organise international Workshops and create a rock physics database website  Commission on Education President: Cai Meifeng (China) Purpose: To organise educational events  Commission on Mine Closure President: Christophe Didier (France) Purpose: To produce a report and book about the stateof-the art with some well documented „case studies‟  Commission on the Preservation of Ancient Sites President: Li Zuixiong (China) Purpose: To encourage exchange of ideas, teaching, research and advancement of knowledge in this field  Commission on Radioactive Waste Disposal President: Wang Ju (China) Purpose: To provide a network for information exchange and to organise workshop/conferences  Commission on Rock Dynamics President: Zhou Yingxin (Singapore) Purpose: To arrange meetings and to co-ordinate rock dynamics research activities within the ISRM community,

Where appropriate the work to date and the intentions of these ISRM Commissions are summarised by the Commission Presidents in the reports in the following pages of this News Journal, pages 32–37. ***** One of the initiatives of the 2007–2011 ISRM Board has been to introduce the concept of ‗Pre-Commissions‘. The idea is to set up Commissions before their period of operation so that they can ‗hit the ground running‘. In other words, if a new Commission is going to be operational during the 2011–2015 period, it makes sense to organise it in the last year of the previous Presidential period, i.e., in 2010 and the early part of 2011, so that it can take advantage of working for the full four-year period. Currently, we have three pre-Commissions as follows.  Petroleum Geomechanics President: Maurice Dusseault (Canada) Purpose: To promote fundamental and practical understanding of rock mechanics as applied to the engineering use of sedimentary basins at depth, accessed by boreholes.  Crustal Stress and Earthquakes President: Xie Furen (China) Purpose: Develop and improve the methods and techniques of borehole-based stress-strain measurements  Commission on Hard Rock Excavation President: Manoj Verman (India) Purpose: Compiling case histories of hard rock excavation projects, especially those from the Himalayas, the Alps and the Andes

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Geophysics Commission

Education Commission

Commission President: Toshifumi Matsuoka, Japan (matsuoka@earth.kumst.kyoto-u.ac.jp)

Commission President: Meifeng Cai, China (caimeifeng@ustb.edu.cn)

1. Commission Objectives

1. Organisation of the 2nd International Young Scholars’ Symposium on Rock Mechanics, October 2011

The objectives of the Commission are 1) to promote geophysical techniques in rock engineering, 2) to organise international Workshops on the application of geophysics to rock engineering, and 3) to establish closer relationships between ISRM members and exploration geophysicists who are interested in the academic field on the application of geophysics to rock engineering.

The background to this 2nd 2011 Symposium is that the 1st International Young Scholars‘ Symposium on Rock Mechanics was held in April 28–May 1, 2008. About 280 experts and scholars who were from 11 countries attended the Symposium. The proceedings of the Symposium were published by Taylor & Francis/Balkema with all 183 papers being covered in databases of both the EI (the Engineering Index) and ISTP (Index to Scientific & Technical Proceedings). The complete success of this 1st Symposium provided the experience to view the International Young Scholars‘ Symposium as a serial conference which will be held every three years. Thus, the Commission on Education decided to hold the 2nd International Young Scholars‘ Symposium on Rock Mechanics in 2011. Because many papers and attendees came from outside China in the 1st International Young Scholars‘ Symposium, the 2nd International Young Scholars‘ Symposium will be held in junction with the 2011 ISRM Congress in Beijing. The first Announcement and Call for Papers of the Symposium has been released on both the ISRM website and the 2011 ISRM Congress website. The main points relating to this 2nd Symposium are that it will be held immediately before the ISRM Congress, in the same venue, i.e., the China National Convention Centre. The language will be English and the themes can be found on the Symposium website. All the accepted papers will be included in the Symposium proceedings, which will be published by Taylor & Francis/Balkema. Further information can be obtained from Prof J A Wang at e-mail: wjarock@ces.ustb.edu.cn

2. Commission Members

The Commission members in the term 2007–2011 are as follows:  Prof. T. Matsuoka (President, Japan)  Prof. E. Brueckl (Austria)  Prof. Xu Chang (China)  Dr. C. Cosma (Finland)  Prof. A. Ghazvinian (Iran)  Prof. P. Hatherly (Australia)  Dr. Jung-Ho Kim (Korea)  Prof. S. King (UK)  Dr. B. Lehmann (Germany)  Dr. S. Lüth (Germany)  Prof. C. J. de Pater (Netherlands)  Prof. L. J. Pyrak-Nolte (U.S.A.)  Dr. E. Sellers (South Africa)  Dr. S. Tanaka (Japan)  Prof. P. Young (Canada) 3. Activity in 2010

The Commission has proposed a Special Session in the ISRM Congress in Beijing 2011 on ―Rock Physics and Geophysics for CO2 Sequestration‖. Because CCS is becoming one of the key technologies for reduction of CO2 emission from the atmosphere, rock mechanics is expected to contribute to it. Geophysics is also expected to play a central role for monitoring and verifying CO2 movement in the ground. Although geophysics has been applied already to several CCS fields, there still remain many challenges to be solved in future. Therefore, we will hold the Special Session on this topic to contribute to future developments of geophysical technologies and rock mechanics for CCS. We plan to invite several Keynote speakers who have been working in this field. The Commission is also planning to hold a workshop on monitoring geophysics and its related topics in conjunction with this Special Session during the ISRM Congress in Beijing, 2011. This workshop is one of the series of the workshops on application of geophysics to rock engineering which have been held from 1990 as an activity of the Commission.

2. Popularisation of the Results of the 2009 ISRM Lecture Tour in China

The 2009 ISRM Lecture Tour in China covered the principles of rock mechanics and the process of rock characterisation, modelling and design for rock engineering. The total lecturing was about 3000 person–lectures. To date, the number of indirect-listening students of the lectures made in the Lecture Tour is estimated to now be more than 5000. 3. The joint work with JTC3

Dr. Marik Kwasniewski has completed the updating work on the ―ISRM Rock Mechanics Curriculum Guide‖ for petroleum rock mechanics 4. Editing a rock mechanics textbook outline

Based on the ―Engineering Rock Mechanics‖ books written by John A Hudson and John P Harrison, the ―Rock Mechanics and Engineering‖ book edited by Meifeng Cai et al., and the ―ISRM Rock Mechanics Curriculum Guide‖ edited by Marik Kwasniewski, the edition of a re-compiled text book/detailed teaching outline of rock mechanics and engineering is in preparation.

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Mine Closure Commission

Ancient Sites Commission

Commission President: Christophe Didier, France (Christophe.Didier@ineris.fr)

Commission President: Li Zuixiong, China (lizuixiong@yahoo.com.cn)

The Mine Closure Commission aims to create links between experts in order to exchange information and experience dealing with the closure of mining works and the management of abandoned mining sites. After having published on the ISRM website an important ―state-of-the-art report on mine closure and post mining management‖, the main objective of the Commission is now to complete the document with a compilation of successful case studies. Some papers have been recently published on the subject by members of the Commission. Recent contacts have been made to enlarge the existing expert panel. The Commission will organise a specialised session on the topic during the next ISRM International Congress in Beijing 2011 with several case studies representative of various countries, contexts and objectives. These examples will be introduced into the existing report to illustrate the mine closure process. Once completed, the optimised distribution of the final report will be considered.

The second Commission meeting was held in association with the ISRM International Symposium for 2009 in May in Hong Kong, China. At that time, a Workshop on the new advances in the field of preservation of Ancient Sites, attended by many noted scholars from over the world was organised successfully. Following that, some main tasks were accomplished as follows: Prof. Coli from the Dept. of Earth Science, University of Florence, Italy was invited to visit the Dunhuang Academy of China. After a field trip and discussion, an ‗Agreement of Cultural and Scientific Co-operation‘ was established between the University of Florence (Italy) and the Chinese Society for Rock Mechanics and Engineering, via the Commission. A field consulting activity relating to the preservation of ancient sites at the Dujiang Yan district after the Wenchuan catastrophic earthquake took place on 12 May 2008. The Proceedings of the International Symposium on the Conservation of Ancient Sites 2008(ISCAS-2008)—the 2008 ISRM Sponsored Regional Symposium containing 79 articles, with an important preface written by John A Hudson and Qian Qihu was formally published by the Science Press of China for international communication. The items currently in progress are as follows.  Collection of major case histories of the preservation of ancient sites worldwide  Listing of publications in the international community  Hosting an international Workshop during the Commission Meeting held in New Delhi, India, during ARMS6 on 24 Oct. 2010. In accordance with the kind proposal put forward by Luis de Sousa, hosting an International Symposium on the Preservation of Historical Forts, jointly organised by the ISRM Commission on the Preservation of Ancient Sites and Portuguese colleagues to be held in Porto, Portugal in 2012. Discussion with Luis de Sousa on the organisation is well progressed. Sincere thanks are due to John A Hudson, President ISRM and Luis Lamas, Secretary-General ISRM, for their kind help and consideration.

Cover of the Mine Closure report which is available for ISRM Members to download from the ISRM website: www.isrm.net

Meeting of the Commission on the Preservation of Ancient Sites

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Radioactive Waste Disposal Commission Wang Ju, China (radwaste@public.bta.net.cn) Overview The purpose and products of the Commission on Radioactive Waste disposal are as follows:  to establish a platform for rock mechanics scientific and information exchange in the field of radioactive waste disposal;  to organise workshops/conferences related to radioactive waste disposal, independently or within the ISRM conference system;  to establish a network for rock mechanics scientists working on radioactive waste disposal;  to provide a scientific advisory system for radioactive waste disposal; and  to explore scientific co-operation with sister societies and relevant organizations, such as IAEG, etc.

John A. Hudson, Ju Wang and Yuemiao Liu

One keynote lecture by Ju Wang and two parallel sessions including ten oral presentations concerning nuclear waste were held during SINOROCK2009 organised by the Chinese Society for Rock Mechanics and Engineering (CSRME) and the University of Hong Kong on 19–22 May 2009. More than 80 participants attended the two parallel sessions about nuclear waste disposal.

The Commission on Radioactive Waste Disposal (CRWD), ISRM, held its first meeting in Hong Kong, China, in conjunction with the symposium SINOROCK 2009 on 18 May 2009. One keynote lecture and two parallel sessions relating to nuclear waste were held during SINOROCK2009. The 3rd National Conference on Underground Waste Disposal was held in Hangzhou, China, on 14–18 September 2010. An International Workshop on ―Radioactive Waste Disposal: Progress and Challenges‖ will be held in Beijing on 16 October, 2011. An ISRM Suggested Method for borehole televiewer measurement, which is one of the most advanced methods for determination of fractures in a borehole, is being prepared. Also, a questionnaire about key facts relating to the site selection of radioactive waste disposal and rock mechanics data from site investigation will be distributed to different countries through the members of CRWD.

The 3rd National Conference on Underground Waste Disposal

The 3rd National Conference on Underground Waste Disposal was held in Hangzhou, China, on 14–18 September 2010. The five sessions included site selection, site characterisation, and safety assessment, rock mechanics, engineered barriers, waste forms and radionuclide migration, and disposal of industrial waste and carbon dioxide. About 150 participants from 50 different organisations attended the conference. The proceedings contain 65 papers and 56 presentations were made. Workshop and Special Session during the ISRM 2011 Congress

An International Workshop on ―Radioactive Waste Disposal: Progress and Challenges‖ will be held in Beijing, China on 16 October (Sunday) 2011. Also, a Special Session will be held during the ISRM2011 on Friday 21 October. A synopsis of the Workshop and Special Session is as follows.

The First Meeting of the Commission on Radioactive Waste Disposal (CRWD) The Commission on Radioactive Waste Disposal (CRWD), ISRM held its first meeting in Hong Kong, China, in conjunction with SINOROCK 2009, organised by the Chinese Society for Rock Mechanics and Engineering and the University of Hong Kong on 18 May 2009. 12 of the 18 Commission members were present: Ju Wang, L. George Tham, John A Hudson, Qian Qihu, Rolf Christiansson, Quanhong Feng, Abbas Majdi, Eda Freitas de Quadros, Stefan Heusermann, Yuemiao Liu and Zihua Zong.

 Worldwide perspectives on radioactive waste disposal, especially relating to the geological disposal of high level radioactive waste  Coupled T-H-M-C behaviour of host rocks for geological repositories  Numerical modelling for underground waste disposal engineering  Performance assessment of geological repositories  Characterisation of fractured media  Time-dependent behaviour of excavation damaged zones  Challenges facing radioactive waste disposal Commission contacts

President: Dr. Ju WANG, China, E-mail: wangju9818@163.com, Secretary: Dr. Yuemiao Liu E-Mail: liuyuemiao@yahoo.com.cn First meeting of the Radioactive Waste Commission in Hong Kong (Rolf Christiansson on the left)

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Rock Dynamics Commission

Design Methodology Comm.

Yingxin Zhou, Singapore (zyingxin@dsta.gov.sg)

Xia-Ting Feng, China (xtfeng@whrsm.ac.cn)

Introduction The terms of reference for the ISRM Commission on Rock Dynamics include the following.  Provide a forum for the sharing and exchange of knowledge in rock dynamics research and engineering applications. This includes organising Commission meetings as well as Workshops, Seminars and Short Courses in connection with ISRM-supported events.  Co-ordinate rock dynamic research activities within the ISRM community, as well as with other research and professional organisations (e.g., the International Society of Explosives Engineers).  Produce reports and guidelines on the study and engineering applications of rock dynamics, covering fundamental theories, dynamic properties of rock and rock mass, testing methods, tunnel response, and support design. The short-term goal is to produce Suggested Methods for Rock Dynamic Testing; the long-term goal is to produce a Guideline on Rock Dynamic Response and Support Design.

Purpose, Work and Product of the Commission The purpose of the Commission has been to develop a manual for rock engineering design methods using both general experience and specific experience from large projects in China, outlining:  methods of design for underground structures in rock masses;  the types of information required to support such rock engineering design;  methods for auditing design procedures, both concurrently with the design process and subsequently; and  illustrative case examples of design and auditing based on major projects in China. The work has been undertaken via an Overseeing Committee, Task Force Committee and the ISRM Commission itself. Task Force Meetings were held on these dates and at these locations: 11 July 2007, Lisbon; 15 August 2007, Beijing; 19 September 2008, Beijing; 29 March 2009, Wuhan; 15 May 2010, Wuhan, 23 August 2010, Beijing. The main work was completed towards the end of 2010 through the completion of a book, see the picture at the bottom of this column. The contents will be presented at a Special Session of the ISRM Congress in Beijing on Friday 21 October, 2011. Xia-Ting Feng and John A. Hudson are extremely grateful to the Commission members for their reviewing contributions: Cai Meifeng, Claus Erichsen, Erik Johansson, Li Zhongkui, Wulf Schubert, Alexandros Sofianos, Ove Stephansson, Tang Chun‘an, George Tham, Resat Ulusay and Thierry You.

Work Plan and Timetable The work plan and schedule of the Commission in the first three years of the Commission‘s tenure, 2007–2011, has been: Year 1 – Appointment of Commission members, preparation and communication of the work plan and work assignments, and initiation of the Commission work: literature review on rock dynamic testing and compilation of rock dynamic properties. Year 2–3 – Preparation of Suggested Methods on Rock Dynamic Testing. Commission Activities for 2010 Following the successful Workshop held in June 2009 in EPFL at Lausanne, Switzerland, and based on the agreements at the Conclusion of the workshop, the Commission has focused its efforts on drafting the Suggested Methods for Rock Dynamics Testing. The Commission, under the coordination of Kaiwen Xia, Xibing Li, and Zilong Zhou, has drafted four suggested methods. They are: 1) Suggested Method for determining the dynamic uniaxial compressive strength of rock materials with the Split Hopkinson pressure bar; 2) Suggested Method for determining the dynamic indirect tensile strength by the Brazilian test; 3) Suggested Method for determining the dynamic flexural strength by the Semi-Circular bend test; and 4) Suggested Method for determining the dynamic fracture toughness. A Workshop was planned for the final review and discussion of these Suggested Methods on 12–13 December 2010 at the Wuhan Institute of Rock and Soil Mechanics, China. Also, a Workshop on Rock Dynamics, WS1, chaired by Kaiwen Xia, will be held in association with the 12 th ISRM Congress held in Beijing, China, on either the Sunday or Monday, 16 or 17 October, 2011.

Published book produced by the ISRM Commission on Rock Engineering Design Methodology (available from www.crcpress.com)

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Rock Spalling Commission Mark Diederichs, Canada (mdiederi@geol.queensu.ca) The Commission on Rock Spall Prediction was initiated in May, 2009, at the SINOROCK conference in Hong Kong. The mandate of the Commission is to develop Suggested Methods for the determination, from laboratory tests, of key parameters for spalling prediction and to provide guidance for the determination of spalling potential for different rock types and rock mass characteristics. Secondary goals include the evaluation of predictive tools for spalling around excavations that are currently available to the practising engineer and to encourage further development of more sophisticated numerical techniques. The current members of the Commission include: Mark Diederichs (Leading Co-President of Commission), Derek Martin (Co-President of Commission), Lars Jacobsson (Sweden), Bernie Gorski (Canada), Matti Hakala (Finland), Dick Stacey (South Africa), Ming Cai (Canada), Christer Andersson (Sweden), Erik Eberhardt (Canada), Florian Amman (Switzerland), Marc Panet (France), and Giovanni Grasselli (Canada) The first definitive act of the Commission was to standardise terminology. In particular, CI is the crack damage initiation threshold for the rock sample. This threshold is marked by the onset of systematically increasing damage (cracks) with increasing applied stress, and can be determined by acoustic emission monitoring or by lateral strain measurements (onset of lateral or circumferential extension strain non-linearity). The threshold marks the lower bound for in situ rock strength, and the likely observable spall initiation threshold for tunnels in massive rock, as well as the lower bound for long term strength, provided this limit is not exceeded during the excavation stress path.

Standardisation of this measurement is also required. CD is the Crack Damage threshold or true yield strength of the rock sample determined from the onset of axial stress–strain non-linearity prior to peak stress (UCS) or is determined from the stress level when incremental volumetric strain reverses from contraction to expansion, see diagram below. This value represents the upper bound for short term in situ strength. The Commission has met in national and regional groups several times over the past year. The Scandinavian and Canadian members met at the BEFO (Swedish Rock Mechanics Society) Workshop in March 2010 to discuss rock testing for spall prediction, as well as key spalling issues associated with nuclear waste repository engineering, and the effects of damage, anisotropy, moisture and/or pore pressure, temperature and intermediate principal stress on CI. Throughout the year, a rigorous testing program has been undertaken and is at last completed. This testing program involved sending 4 sets of 10 samples (Smaland Granite) to 4 independent labs for CI (crack initiation), CD (crack damage) and UCS measurement using their state-of-practice techniques, including various strain measurement and calculation procedures, as well as acoustic emissions. These test results are now being compared and analysed by separate teams directed by Derek Martin (University of Alberta, Canada) and Mark Diederichs (Queen‘s University, Canada). The next meeting of the Spalling Commission will take place in association with the 2011 Beijing Congress being held in October 2011.

Using the uniaxial compression test with stress, strain and acoustic emission transducers to establish the CI and CD values

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ISRM Testing Methods Commission Resat Ulusay, Turkey (resat@hacettepe.edu.tr) WG for Upgraded SM for Determining Shear Strength, both in Field and Laboratory, and SMs on the Shear Strength of Rock Joints and Shear Testing including Stiffness Controlled Tests Chairman: Jose Muralha, Portugal The WG has a draft of the Suggested Method for Laboratory Determination of the Shear Strength of Rock Discontinuities and it has been sent to other members for suggestions and upgrades. The WG chairman included the contributions of other members in late 2010. It will be possible to have the final document included in the Orange Book.

Based on the information from the Chairmen, the activities of the new Working Groups (WGs) preparing new and upgraded Suggested Methods (SMs) are given below. WG for SMs on Failure Criteria Co-Chairmen: Bezalel Haimson and Antonio Bobet, USA This WG completed the draft documents in May 2010 and submitted them to the Commission for reviewing. The documents are now under review. In the case of their acceptance, they will be submitted to the IJRMMS for publication and will be included in the ‘Orange Book‘, the successor to the Blue Book. This SM consists of the following parts:  Introduction (Co-Chairmen: Bezalel Haimson, Antonio Bobet)  Mohr–Coulomb criterion (Joe Labuz, Arno Zang)  Hoek–Brown criterion (Erik Eberhardt)  True triaxial strength criterion (Chandong Chang, Bezalel Haimson)  Drucker–Prager criterion (Leandro Alejano, Antonio Bobet)  Modified Lade criterion (Sergio Fontoura)  3-D failure criteria based on the Hoek–Brown criterion (GZZ, GPH, GP, SP) (Stephen Priest)

WG for Representing the ISRM Suggested Methods in Electronic Form (RISMEF) Chairman: Zuyu Chen, China The final draft SM will be sent to the Commission in 2011. WG for SM for Determination of Thermal Properties Chairman: Dr. Bijan Adl-Zarrabi This most recently established WG is at the beginning stage of its work. WG for SM for the Abrasivity Test Chairman: Helko Kasling, Germany This is another newly formed WG and Dr. Kasling is submitting a proposal .

WG for SM on Mode II Fracture Toughness” Chairman: Ove Stephansson, Germany This WG has also completed its final document and submitted it to the Commission in June 2010. The final version will be submitted to the IJRMMS for publication and will be included in the Orange Book as an ISRM SM. The document consists of the following: Introduction, Scope, Specimen preparation, Experimental set-up, Workflow, Evaluation of experiments, Reporting results, Acknowledgements, Notes and recommendations, References.

Volunteers who are interested in the abrasivity topic, may contact the President of the Commission, Resat Ulusay

Commission on Rock Dynamics (see also p. 35) President: Yingxin Zhou This Commission has prepared four separate SMs on dynamic rock testing. These were discussed at the 6th Asian Rock Mechanics Symposium in New Delhi in October 2010 and will be published in the Orange Book.

WG for SMs on the Creep Test Chairman: Omer Aydan, Japan The members of the Working Group were reorganised and some advisory members, with the consideration of the participants at the WG meeting in Tehran, were added: S. Sakurai, Japan; Nuno Grossman, Portugal; Wolfgang Wawersik, USA; and Eda de Quadros, Brasil. The first draft of Suggested Methods for creep tests has been completed by the core members and distributed to all members for consideration in August, 2010.

***** There will be a Special Session on Testing Methods held at the ISRM Congress in Beijing on Friday 21 October 2011.

Most readers will have seen the ‗Blue Book‘ which was published in 2007 and contains all the ISRM Suggested Methods generated from 1974 to 2006.

WG for SM on Standard Practice for Displacement Measurements Using a Global Positioning System Chairman: Norikazu Shimizu, Japan The final draft SM was submitted to the Commission in January 2011.

The ‗Blue Book‘ is to be followed by the ‗Orange Book‘ which will contain all the Suggested Methods produced since 2006, together with other relevant material.

WG for Upgraded SM for Sonic Velocity Test Chairman: Adnan Aydin, USA The final draft SM was submitted to the Commission at the end of 2010.

The ‗Orange Book‘ will be available at the May, 2012 EUROCK Symposium to be held in Stockholm, Sweden.

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Introduction to the Technical Articles on In Situ Stress John A. Hudson, UK (john.a.hudson@gmail.com) In this Issue, the technical articles concern in situ stress and have been kindly provided in condensed form by the authors who presented them at the ISRM 5th International Symposium on In Situ Rock Stress held in Beijing, China on 25–27 August 2010 under the leadership of Furen Xie of the Institute of Crustal Dynamics, China Earthquake Administration, Beijing China. The Symposium was very well attended with many papers being presented. The cover of the proceedings, edited by Furen Xie, is shown in the photograph below and contains 877 pages. There have been four previous international symposia on in situ rock stress as follows: Stockholm, Sweden 1986; Kumamoto, Japan, 1993; Kumamoto, Japan, 2003; Trondheim, Norway, 2006. In addition, there have been two in situ stress Workshops held in Minneapolis and Madison, USA.) These in situ rock stress symposia were arranged on an ad hoc basis, i.e., they were not arranged by any overseeing committee. However, the 2010 Symposium described in the paragraph above was sponsored by the International Society for Rock Mechanics (ISRM) as a Specialised Conference—which is a category recently introduced by the ISRM specifically for a Symposium having a specialised theme. The ISRM has taken on the responsibility for selecting the venues of forthcoming in situ stress symposia, and the next one will be organised by Takatoshi Ito as an ISRM Special-

ised Conference and held in Japan at Tohoku University in early September, 2013. The subject of in situ stress is particularly important for rock mechanics and rock engineering because the magnitude and orientation of the in situ rock stress components are required for the design of underground rock engineering projects. In recent years, there has been a move to use numerical modelling/simulation methods in conjunction with rock mass classification as the main support for rock engineering design. All these numerical methods require information concerning the in situ stress at the project site as boundary condition information. So, there has been an increased requirement to establish the local site stress conditions during the site investigation process. The origin of in situ rock stress is the movement of the Earth‘s tectonic plates and the presence of any overburden. There can be additional causes of stress, such as water pressure and heat. It is not surprising, therefore, that many in situ stress estimation campaigns encounter problems— not only in the actual measurement procedures but because the in situ stress can vary significantly within and between boreholes at the same site. This then raises questions about the stress measurement techniques and indeed which values to assume for the in situ stress field parameters for the numerical modelling. There is in situ stress variability in relation to the tectonic/regional scale, site scale, excavation scale, borehole/measurement scale, and microscopic scale and the factors causing the variability are rock inhomogeneity, rock anisotropy, discontinuities and free faces. However, the papers submitted to the Beijing 2010 stress meeting have clarified many points and it is hoped that our enhanced understanding will lead to a more coherent approach to the subject through an understanding of the host geology and the associated numerical modelling—leading to guidance on the degree of stress variation that would be expected at a particular site and hence how to approach a stress estimation campaign. The technical articles presented in the following pages certainly help to explain many points and, on behalf of the ISRM, I should like to thank the respective authors for their inclusion.

Proceedings of the ISRM sponsored Symposium held in Beijing, China on 25–27 August, 2010

Ove Stephansson and Bezalel Haimson study the cover

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Tectonic Stress and Strong Earthquakes in China Furen Xie,Hongyan Zhang, Yi Du, China (xxiefr@263.net) INTRODUCTION The research into lithosphere stress is an important branch of earth science. In the late 1980s, the international lithosphere plan headed by Mary Lou Zoback (1992) began the process of compiling the world stress map and this project attracted many scientists from different countries. The map reflects the global and regional characteristics of lithospheric stress field and explains the situation of force action in the lithosphere. One of the important results is that tectonic stress field has uniform characteristics on a large scale inside some plates. The other important result is to recognise that there are first order and second order stress fields inside the plate. In recent years, Chinese researchers have also done a lot of research work about the tectonic stress field (Deng Q.D. et al. 1979, Xu Z.H. et al. 1989, Kan R.J. et al. 1977, Xue H.Y. et al. 1984, Wang S.Y. et al. 1991, 1993, Xie F.R. et al. 1993, 1999, 2003, Cui X.F. et al. 1999, Xu Z.H. 2001). Research indicates that the crustal stress state has a close relation to earthquake activities. In compiling the ―Basic database of crustal stress environment in China‖, we summarise the basic characteristics of the recent, tectonic stress field in China (Xie F.R. et al. 2003), divide it into the tectonic stress districts, and preliminarily analyse the relation between the recent tectonic stress field and strong earthquakes.

Tectonic stress districts in China Using this method and process, we obtain two first order districts, four second order districts, five third order districts and 26 fourth order districts (Fig. 1, Tab. 1). From Figure 1 and Table 1, we can see clearly that the East China district and the West China district—the two first order districts— are divided by North-South Seismic Zone. In the East China district, there are two second order stress districts, named NorthEast-North China and South China. They are divided by the Qinling Fault Zone. The NorthEast-North China stress district contains two third order stress districts, the boundary of which is the Yinshan-Yanshan-Bohai Fault Zone. In total, there are 13 fourth order stress districts in the East China district and they are divided by different fault zones. In the West China district, there are also two second order stress districts, named Xinjiang and Tibet. The boundary of these is the Xikunlun-Aerjin-Qilianshan Fault Zone, which meets with the North-South Seismic Zone at its eastern end. In the Tibet stress district, it consists of the Himalayan, South Tibet and North and East Tibet 3 stress districts, and the boundary of these three stress districts is the LazhulongJinshajiang-Honghe Fault Zone and Yaluzangbujiang Fault Zone. But there is no third order stress district in Xinjiang. There are 18 fourth order stress districts in the west China district in all.

TECTONIC STRESS DISTRICTS IN CHINA The principle and process of tectonic stress zoning Based on the mechanical properties and deformational behaviour of tectonic stress and its force sources, the principle of tectonic stress zoning is as follows. Firstly, the direction of the principal compressive stress in each tectonic stress district must be consistent. Secondly, the stress regime in each tectonic stress district must be similar. Thirdly, the stress intensity in each tectonic stress district should be basically equal. Fourthly, the tectonic deformation and the failure mode of faulting in each stress district should be similar. And lastly, the dynamic force source of different stress districts with the same order in one tectonic stress district should be identical. According to the above principles of tectonic stress zoning, we initially divide up the tectonic stress districts in China, and then we use the ―Step by Step Convergence Method (SSCM)‖ (Cui X.F. et al. 1999) to screen each focal mechanism solution according to two criteria.  One is whether the angle between the fault slip vector and the direction of shear stress due to the deviatoric stress tensor acting on the seismic fault plane is less than or equal to 30°.  The other is that the ratio of shear stress of the deviatoric stress tensor acting on the fault plane to the stress on the same fault plane must be greater than or equal to 0.51. Thus, we can determine which earthquakes are controlled by one homogeneous tectonic stress field and at last we decide the boundary of each tectonic stress district, which is useful for districts with ambiguous boundaries.

Figure 1. Recent tectonic stress districts in China.

THE RELATION BETWEEN TECTONIC STRESS DISTRICTS AND STRONG EARTHQUAKES IN CHINA Regions where there is intense tectonic stress action and a complex stress distribution are the areas where strong earthquakes happen frequently. These regions, such as the Qinghai-Tibet Plateau and Taiwan, where there is the most intense plate collision, have the earthquake activities of the largest intensity and the highest frequency. And in the North China and Xinjiang regions, the stress distribution is complex and strong earthquakes happen more frequently.

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Tectonic Stress and Strong Earthquakes in China (cont) According to the compiled earthquake catalogue (Department of Seismic Hazard Prevention and Mitigation, China Earthquake Administration, 1999) and the statistical data of earthquake distribution in China (Fig. 2), it is found that more than 70% of the earthquakes with magnitude greater than 4.0 are in the Qinghai-Tibet Plateau and Taiwan stress districts, more than 20% are in the north China and Xinjiang districts, but in south China and the NorthEast stress districts the percentage is only about 6%. Among them, more than 75% of earthquakes with magnitude greater than 6.0 are in the Qinghai-Tibet Plateau and Taiwan stress districts, about 20% are in north China and in the Xinjiang districts, but in South China and the NorthEast stress districts there are less than 5%. Thus, it can be seen that earthquake activities and the tectonic stress background have a very close relation. An area with intense tectonic stress action and a complex stress distribution type is the main location where earthquakes happen easily and frequently.

Figure 3. Inversion results from fault slip data in the Longmenshan fault.

Figure 3 is the inversion result from fault slip data in the Longmenshan fault after the Wenchuan earthquake. We can see clearly from Figure 3 that the principal compressive stress in this region is about in the East-West direction, and the stress regime is that of reverse slip. From the point of view of the force source, the source of the eastern China stress district comes mainly from the united action produced by the Pacific plate subduction beneath the Eurasian continent towards the West and the Philippine plate subduction beneath the Eurasian continent towards the North-West. The source of the western China stress district comes mainly from the Indian plate colliding with the Eurasian continent towards the North. Therefore, through the united action of the above three plates, the primary characteristic of the recent tectonic stress field in the Longmenshan region is nearly East-West. Another good example is the Yushu earthquake, Figure 4. On 14 April 2010, the Qinghai Yushu earthquake occurred on the Ganzi-Yushu fault, which is one of the branches of the Jinshajiang-xianshuihe fault zone. In the context of global plate movement, this earthquake occurred at the Qinghai-Tibet Plateau formed by the Indian plate pushing the Eurasia continent towards the North. The Qinghai-Tibet Plateau gradually becomes shortened under the pushing action and, at the same time, the interior blocks begin to slip in the lateral direction along faults at the boundary of the stress districts. This makes the main block of the QinghaiTibet Plateau move towards the East and some strike-slip fault systems and extrusion blocks at a different scale form inside or at the edge of the Qinghai-Tibet Plateau. From the point of view of the fault zone, the Yushu earthquake happened on the Jinshajiang-xianshuihe fault zone

Figure 2. The distribution of strong earthquakes and tectonic stress districts in China and its adjacent areas.

The boundary of stress districts is the zone where strong earthquakes occur frequently Because of the intense tectonic action and complex stress distribution, the boundary of the stress districts is the location where strong earthquakes happen most easily and frequently. In mainland China, the two first-order stress districts controlled by the dynamic action of plates are the eastern China stress district and western China stress district, the boundary between them being the North-South seismotectonic belt (Fig. 2). On 12 May 2008, the Wenchuan earthquake shocked all the world. It occurred on the Longmenshan fault which belongs to the North-South seismotectonic belt, this being a first-order boundary of stress districts.

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where tectonic deformation intensity alters. Take the periphery of the Sichuan-Yunnan active block in South-West China for example: the principal compressional stress direction and the stress regime of the recent tectonic stress field have apparent differences (Fig. 5). For the Sichuan-Yunnan active block itself, its main tectonic principal stress direction is in the NNW–SSE direction and the stress regime is strike-slip. However, in the Songpan-Longmenshan region at the North-East of the Sichuan-Yunnan active block, the tectonic principal stress direction is NEE–SWW, and its stress regime is reverse-slip. In the South China block, which is at the east of the Sichuan-Yunnan block, its tectonic principal stress direction is SSE–NWW, and the stress regime is strike-slip (Xie F.R. et al. 1993, 1999). The Xianshuihe fault zone, located between the SichuanYunnan active block and the Songpan-Longmenshan region, and the Anninghe-xiaojiang fault zone, located between the Sichuan-Yunnan active block and the south China block, are the sectors where strong earthquakes focus (Fig. 5). The Tienshan seismic zone is located in the transition zone where the tectonic deformation varies from weak to strong. This is a typical example where earthquakes occur because the tectonic stress intensity is transformed. In addition, there are more earthquakes occurring in the areas having a higher stress value, but with the same tectonic background and stress field surroundings—such as the region in the North-West of Yunnan where the major principal stress values at the depths of 320–450m are 23.4 MPa, 22.9 MPa and 30.2 MPa in Lijiang, Jianchuan and Xiaguan, respectively. But at the same depth, the stress value is just 15 MPa at the Yongping measuring point. It is the locations above where strong earthquakes occur frequently.

Figure 4. Recent tectonic stress field and strong earthquake distribution in Yushu, Qinghai area, China.

which is a third-order boundary of the stress districts. The mean Holocene horizontal slip rate of the Jinshajiangxianshuihe fault zone is 5–7mm/annum and the mean horizontal slip rate of the Kalakunlun-jiali fault zone located in the north of the Bayankala block is 10–11mm/annum. Both the fault zones are in the East-West direction and gradually push towards the East. This causes the Shichuan-Yunnan region, stopped by the Yangtze block, to generate complex fault deformations and block rotations, and could be one of the reasons for the occurrence of the Kunlunshan earthquake, Wenchuan earthquake (with magnitudes of 8.1 and 8.0, respectively) and several other large earthquakes (with magnitude equal or greater than 7). Because of the united action controlled by different plates, the recent tectonic movements of the boundary of different stress districts in China, especially the North-South seismotectonic belt, are strong and active. From North to South, there is a series of active tectonic zones, such as the West edge of the Ordos fault zone, the Haiyuan-Liupanshan fault zone, the east Qinling fault zone, the Minjiang fault zone, the Longmenshan fault zone, and the Xianshuihe-zemuhexiaojiang fault zone. These boundary zones are the locations of the strongest earthquake activities in China. Stress districts where strong earthquakes occur frequently The whole of the Chinese continent is divided into 23 seismic zones (Huan W.L. et al. 1998). More than 90% of the destructive earthquakes in China occur in these seismic zones. The present seismic zones not only have obvious geological structural characteristics, but also have apparent variational characteristics in the tectonic stress direction, stress regime and stress value. Thus, it can be seen that the seismic zones are closely related to the variation of the tectonic stress field. Among the 23 seismic zones, there are 12 zones where the tectonic principal stress direction changes, 10 zones where the stress regime varies, and 21 zones

Figure 5. Tectonic stress field and strong earthquake distribution in Sichuan-Yunnan active block and its periphery.

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Tectonic Stress and Strong Earthquakes in China (cont) Stress districts with local changes but within the homogeneous stress background are the places where strong earthquakes occur frequently Stress districts with local differentiation within the even stress background have stronger earthquakes. For example, the primary characteristics of the tectonic stress field in north China is that its principal compressional stress direction is in the NEE–SWW direction and most of the stress regime is strike-slip (Fig. 6). However, the tectonic stress in the Fen-Wei fault zone, located in the middle of North China, is tensile, and the stress direction and stress regime are apparently different from the total North China region (Xie F.R. et al. 2003). Figure 7. The tectonic stress field and strong earthquake distribution in the Tienshan region. Tibet Plateau, the crustal material is blocked as the TarimTienshan and Alasan blocks move towards the East or South-East and form a tectonic environment with the characteristic of shear stress action. A number of well known strike-slip fault zones have been formed, such as the Altun fault zone, East Kunlun fault zone, Xianshuihe fault zone. The shear-tensile tectonic environment in North China results from the combined action of the northward pushing of the Indian Plate and the westward subduction of the Pacific Plate (Fig. 8). Under this action. North-East trending faults are dextral with a normal component, while West-North trending faults are sinistral with a normal component as well. North-East China is mainly affected by the east subduction of the Pacific Plate, resulting in a shear–compression tectonic environment; and, in this region, the North-East trending faults are dextral, or dextral with a reverse component, but the North-West trending faults are sinistral or sinistral with a reverse component. South China is mainly affected by the northward pushing of the Philippine Plate forming a shearcompression tectonic environment (Fig. 8). Under this tec-

Figure 6. Tectonic stress field and strong earthquake distribution in North China. Another good case is the Tienshan stress district. From Figure 7, it can be seen that the main direction of the maximum compressional stress in the Tienshan area is in the ~N–S direction and the stress regimes are almost strike-slip and reverse- slip. However, besides the main group of stress directions in the Pamirs and Jiashi region, another group of stress directions are mainly in the NNE–SSW direction. The change of stress state can cause an heterogeneous distribution of stress accumulation and, in that case, it can cause strong earthquakes concentrated on a loction to occur. DISCUSSION AND CONLUSIONS The pattern of tectonic stress districts in China is obviously controlled by the dynamic action of peripheral plates. The collision between the Indian plate and Eurasian continent is the primary dynamic factor that helps to establish the basic pattern of recent tectonic stress field in China (Fig. 8). The Indian plate collides with the Eurasian continent towards the north at a displacement of 50 mm every year (Ding G.Y. et al. 1988), and the southern part of the Tibetan Plateau is greatly pressurised at first. As a consequence, it uplifts quickly and creates a horizontal stretching on the upper crust of the plateau. At the North-East edge of the Qinghai-

Figure 8. Dynamic force sources from adjacent plates acting on the Eurasian Plate.

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of China seismic zoning. Beijing: Seismological Press, 1026 (in Chinese). Wang Suyun & James Ni & Ma Zongjin, et al. 1991. The characteristics of fault plane solutions and focal depths of strong earthquakes in North China. Chinese J. Geophys. (Acta Seismologica Sinica), 34(1): 42-54. Xie Furen & Chen Qunce & Cui Xiaofeng, et al. 2003. Research on crustal stress state in China and adjacent area. Beijing: Geological Press, 10-26 (in Chinese). Xie Furen & Zhang Shimin & Dou Suqin, et al. 1999. Evolution characteristics of Quaternary tectonic stress field in the north and east margins of Qinghai-Xizang plateau. Acta Seismologica Sinica, 12(5): 550-561 (in Chinese). Xie Furen & Zhu Jingzhong & Liang Hai-qing, et al. 1993. The Basic Characteristics of Recent Tectonic Stress Field in Southwest Region of China. Acta Seismologica Sinica, 15(4):407-417 (in Chinese). Xu Zhonghuai. 2001. A present-day tectonic stress map for Eastern Asia region. Acta Seismologica Sinica, 23(5): 492 -501 (in Chinese). Xu Zhonghuai & Wang Suyun & Huang Yurui, et al. 1989. The tectonic stress field of the Chinese continent deduced from a great number of earthquakes. Chinese J. Geophys. (Acta Seismologica Sinica), 32(6): 636-647 (in Chinese). Xue Hongyun & Yan Jiaquan. 1984. The contemporary stress field around the Ordos Block. Chinese J. Geophys. (Acta Seismologica Sinica), 27(2):144-152 (in Chinese). Zoback M L. 1992. First- and second-order patterns of stress in the lithosphere: the world stress map project. J. Geophys. Res., 97(B8): 11703-11728. Department of Seismic Hazard Prevention and Mitigation, China Earthquake Adminstration. 1999. Recent earthquake catalog in China (1912-1990 A.D.), Beijing: The Science Press of China.

tonic action, the North-West trending faults are dextral and the North-East trending faults are sinistral, or sinistral with a reverse component. According to the stress state and force source characteristics, the tectonic stress field in China is initially divided into four classes. By analysing the relation between the tectonic stress districts and strong earthquakes, a close relation is mainly summarised as follows.  The boundary of the stress districts, especially the first and second order boundaries, are controlled by the interaction of tectonic plates and have stronger earthquakes.  Stress districts with stress direction, regime type and stress value transformation are concentrated zones for strong earthquakes.  Stress districts with local stress differentiation, but with a homogeneous stress background, are the places where strong earthquakes have been concentrated. ACKNOWLEDGEMENTS This work was partially supported by a grant from the National Natural Science Foundation of China (40904024) and a special item of the professional fund for basic scientific research of the Chinese Central-Level Public-Welfare College/Institute from the Institute of Crustal Dynamics, China Earthquake Administration (ZDJ2009-17) to H. Zhang, as well as a grant from the special item of professional fund for basic scientific research of the Chinese Central-Level Public-Welfare College/Institute from the Institute of Crustal Dynamics, China Earthquake Administration (ZDJ2007-1) to F. Xie.

REFERENCES Cui Xiaofeng & Xie Furen. 1999. Preliminary Research on Regional Division of Stress Field from Focal Mechanism Solutions in Southwest China and Its Adjacent Area. Acta Seismologica Sinica, 12(5):562-572 (in Chinese). Deng Qidong & Zhang Yuming & Xu Guilin, et al. 1979. On the tectonic stress field in Chhina and its relation to plate movement. Seismology and Geology, 1(1):11-22 (in Chinese). Ding Guoyu. 1988. The some problems about active tectonic in Tibet Plateau. Northwestern Seismological Journal, 10 (Supplement), 1-11 (in Chinese). Huan Wenlin & Zhang Xiaodong & Wu Xuan, et al. 1998. The research on division of seismic zone in China. Corpus of academic symposium of China Seismic Zoning, Beijing: Seismological Press, 129-139 (in Chinese). Kan Rongju & Zhang Sichang & Yan Fengtong, et al. 1977. Present tectonic stress field and its relation to the characteristics of recent tectonic activity in Southwestern China. Chinese J. Geophys. (Acta Seismologica Sinica), 20(2): 96-108 (in Chinese). Wang Suyun & Gao Ajia & Xu Zhonghuai. 1993. The characteristics of focal mechanism solutions in China and Xie Furen presenting his paper at the adjacent area. In: Department of seismic hazard preven- 5th International Symposium on In Situ Rock Stress (ISRSV) tion and mitigation. State Seismological Bureau. Corpus in Beijing in 2010.

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A Global Stress Interpretation Model L.N. Lamas, J. Muralha & B. Figueiredo , Portugal (llamas@lnec.pt ) INTRODUCTION Release of the state of stress is often the most relevant action during an underground excavation, and it can affect the location and orientation of the cavern or tunnel, the design of the support, as well as the construction method used. The large number of factors that influence the in situ stresses in rock masses make its characterisation a difficult task. These factors include lithological and deformability heterogeneities, topography and the existence of nearby excavations, the action of water, the mechanical properties of rocks or even the actions of man. Owing to these factors, the state of stress presents a significant spatial variability and its characterisation requires execution of in situ tests using the most appropriate test techniques and a global interpretation model for analysis of the obtained results. Several authors have presented descriptions, limitations and fields of application of existing test techniques (e.g., Cornet 1993; Amadei & Stephansson 1997; Fairhurst 2003; Hudson et al. 2003; Ljunggren et al. 2003), which are usually grouped as follows:  methods based on hydraulic fracturing;  methods based on the complete stress release;  methods based on the partial stress release; and  methods based on the observation of the rock mass behaviour. LNEC uses small flatjacks (SFJ) when there is direct access to the rock mass inside adits or wells, and a 3D cell (Strain Tensor Tube – STT) to perform overcoring tests, when the zones of interest can only be reached using boreholes. SFJ is a method of partial stress release. It consists in cutting a 10 mm slot in a rock mass surface with a circular disc saw, introducing a flatjack into the slot and applying a pressure until the deformation caused by opening of the slot is compensated. A single stress component is obtained. STT is a complete stress release method that allows for determining all stress components at a given location using a borehole overcoring technique. STT cells are 2 mm thick epoxy resin hollow cylinders with 10 embedded strain gauges at their mid-thickness, sampling homogeneously the 3D space (Pinto 1983). The cell is cemented in a 37 mm diameter borehole and the in situ stresses are released by overcoring with a larger diameter, thus obtaining a 120 mm diameter core. Strains are measured before and after overcoring and the stresses are calculated using the elastic constants obtained in a biaxial test of the recovered core with the STT cell.

pointwise nature of stress, only allow for characterising the state of stress, or in some cases just some of its components, in the precise locations where they are executed. After the interpretation of the results of each test (as in STT tests), or of sets of tests (as in SFJ tests), it is useful to apply global models that integrate the results from various tests performed in different locations. These models are used to assess the influence of the main factors that affect the stress distribution in rock masses, namely the ground surface topography generated by tectonic or eroding processes, the existence of underground or surface excavations, as well as the heterogeneity and the variability of the mechanical properties of the rock mass. The influence of these factors can be considered jointly or separately. Global interpretation models start by establishing a set of assumptions regarding the stresses in the rock mass. In some cases, based on the particular geometric conditions of a given problem, it may be reasonable to set forward some assumptions regarding the directions of the principal stresses. Assumptions regarding the variation of the stress components may also be justified. It is common to consider that the vertical and horizontal stresses increase linearly with depth, since the stresses are, in a large proportion, due to the weight of the overlaying ground. The global interpretation model used in the analyses presented in this paper is based on the following assumptions.  The natural in situ stress is calculated for an initial situation, prior to the disturbance in the stress field caused by significant topographic changes, such as the excavation of a deep canyon by a river, or caused by any underground excavations in the area of interest.  The principal initial in situ stresses σj0 are zero at the ground surface and vary linearly with depth: σj0 = kj γ h, where γ is the unit weight of the rock mass, h is the depth and j is an index that takes the values 1, 2 and 3.  One principal initial in situ stress is vertical, and therefore the other two are horizontal. The existing natural stress field results from the initial stress field, characterised by the parameters kj, and from the effect of the surface and underground excavations that disturbed the initial conditions. It is calculated through the application of analytical solutions in simple problems or, in the more complex cases, using 3D numerical models. The parameters ki are determined from the measured stress components obtained in all in situ stress measurements, which may have been carried out in different locations and using different methods, and from the geometry of the excavations, using the following methodology, which is derived from a procedure proposed by Sousa et al. (1986):

GLOBAL MODELS FOR THE IN SITU STRESSES IN ROCK MASSES Tests for determination of the in situ stresses in rock masses are usually scarce in number and their results, due to the

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 A vector Mi is constructed with all the measured stress components, where i is an index that takes values from 1 to N.  Each of the three principal initial in situ stresses, with unit kj values, is considered separately, and this corresponds to three loading cases Ei.  Each loading case Ei is applied to the rock mass model, and the stress components at the measuring points are calculated (six for each overcoring test, plus one for each flat jack test).  A matrix Aij is constructed, which represents the N stress components at the different measuring points, for each loading case Ej.  Using the principle of superposition of effects, the following expression can, then, be written:

Aij k j  M i

Figure 1. Layout of the Picote II re-powering scheme (in red).

where (i = 1, 2,…,N) (j = 1, 2, 3) (1) This system of linear equations is usually highly redundant. Its resolution by the least squares method enables one to determine the parameters kj, with which it is possible to calculate the most probable in situ state of stress at any point in the rock mass.

house cavern is 68 m long, 23 m wide and 58 m high at the turbine hall. The cavern is located 150 m below surface and only 80 m away from the existing one. To characterise the in situ stresses, three STT overcoring tests were performed in each of two parallel boreholes (STT1 and STT2), drilled from an existing adit (LNEC 2006). The boreholes are 50 m apart and dip 70º. The tests were carried out at the following depths: STT1: 39.80 m, 66.10 m and 78.35 m; STT2: 41.00 m, 60.60 m and 77.45 m. In all tests, one of the principal stresses was approximately in the direction of the borehole and the other two were approximately parallel and normal to the river axis. In some tests, stress levels were considerably higher than initially expected, especially taking into account the rock coverage. This is the case of the test in STT1 at 78.35 m with an almost hydrostatic stress of around 20 MPa. In this example, the main factor that affects the in situ stresses distribution within the granitic rock mass is the topography of the steep river valley. For the interpretation of the test results, a 2D numerical model was developed, using the finite difference software FLAC (Itasca 2005). The model considers a vertical cross-section of the rock mass in the zone of the new powerhouse, approximately perpendicular to the river and parallel to the boreholes. The mesh has 1,000 m in the horizontal direction, 700 m in the vertical direction from elevations 0 to 700 m, and an axis of symmetry on the left boundary, which represents the river bed. The mesh has 200×300 zones, and is more refined close to the test locations with 2.5 m×1.75 m zones (Figure 2). The associated system of co-ordinates has axis 1 horizontal, in the plane of the model, axis 2 vertical, and axis 3 normal to the plane.

APPLICATION EXAMPLES LNEC was asked to perform in situ stress measurements in rock masses for the design of the ‗re-powering‘ projects of the Picote II, Bemposta II and Salamonde II hydroelectric projects, in the North of Portugal. These re-powering projects consist the construction of new hydraulic circuits and larger underground powerhouses close to the dam valleys. The state of stress in the vicinity of the powerhouses is influenced by the topography of the ground, in particular by the shape of the river valleys, which result from the erosive action of the river over geologic time. In addition, in some cases, the results of tests do not reproduce directly the natural stresses, since they were determined near underground openings that change the stress field around them. To interpret the results of various tests in order to obtain an estimate of the natural stress fields, it was necessary to perform global analyses, making use of numerical models. Picote II re-powering scheme The existing Picote hydroelectric scheme, on the Douro River, consists of a concrete arch dam and an underground powerhouse with a hydraulic circuit in the right bank of the river. The re-powering scheme is also to be built in the right bank, close to and surrounding the existing power plant, and includes a new hydraulic circuit (a 300 m long headrace tunnel and a 150 m long tailrace tunnel), a larger powerhouse cavern and several adits (Figure 1). The new power

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A Global Stress Interpretation Model (cont) mined: k1=1.70 and k3=1.75. Figure 3 shows the principal stresses calculated in the overcoring test locations. The stresses are clearly influenced by the proximity of the canyon. The ratio of σI (sub-horizontal) over σIII (subvertical) is very high (between 4.5 and 5.1). Based on this analysis, recommendations to the designer regarding the state of stress to consider in the powerhouse cavern calculations were issued.  The initial in situ state of stress should be obtained from an initial situation prior to the excavation of the valley, with a vertical stress equal to the weight of the overlying rock mass and with isotropic horizontal stresses equal to 1.75 times the vertical stress.  This initial in situ state of stress shall be considered for simulation of the excavation of the valley due to the erosive effect of the river, and the resulting state of stress shall be the starting point for the design computations of the powerhouse. Owing to the high horizontal stresses calculated and to the relatively scarce information obtained at the design phase, it was decided to perform additional stress measurements, using the small flatjack method, once excavation of the adits reached the proximity of the underground powerhouse. These tests confirmed the existence of high horizontal stresses (about four times the vertical stresses), thus confirming the results obtained in the earlier stages.

Figure 2. Mesh detail and location of the boreholes. The global interpretation method presented earlier was used for calculation of the in situ stresses, with the following additional assumptions:  the rock mass is continuous, linearly elastic, homogeneous and isotropic, with  = 27 kN/m3;  the initial in situ stress corresponds to the situation before excavation of the river valley;  the initial vertical stress σ20 is equal to the weight of the overlying rock (k2 = 1);  the depth h is measured from elevation 700 m;  plane strain conditions. Applying this procedure to the overcoring tests carried out for the Picote II project, the following values were deter-

Bemposta II re-powering scheme The Bemposta II hydroelectric scheme lies downstream from Picote II on the Douro River. The re-powering project includes a new hydraulic circuit and a new powerhouse, which is an 80 m high and 30 m diameter shaft. Test measurements for design of the excavations took advantage of the existence of adits used during construction of the existing powerhouse. In one of these adits, two locations were selected (Fig. 4):  location 1, at the river bed level, at a depth of 95 m, 120 m from the river axis;  location 2, at a level 20 m higher than location 1, at a depth of 130 m, 225 m from the river axis. The adit cross section at location 1 is normal to the river and at location 2 is parallel to the river. At location 1, three small flat jack tests were performed on the adit wall and three overcoring tests were performed in a borehole STT1, perpendicular to the adit wall and dipping 45°. At location 2, three flat jack and two overcoring tests were performed. Borehole STT2 for the overcoring tests was also perpendicular to the wall and dipped at 45°. The main factor that affects the in situ stress distribution within the rock mass is the topography of the river valley. Also, the tests were done close to the adit, which affects the

Figure 3. Stresses in the overcoring test locations.

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Figure 5. Numerical model (2D) with the terrain topography before and after the river eroding effect.

Figure 4. Layout, Bemposta II re-powering scheme. local stress field. Furthermore, two different types of test were used and they were performed at two distinct locations. Estimation of the stress field for design of the underground openings requires, therefore, a global interpretation model that integrates all the information. The global interpretation method presented earlier was used for calculation of the in situ stresses, with the following additional assumptions:  the rock mass is continuous, linear elastic, homogeneous and isotropic, with ď § = 27 kN/m3; and  the initial in situ stress corresponds to the situation before excavation of the river valley. For modelling this situation a 3D numerical model is necessary. However a global 3D model would be very large and difficult to handle. To overcome this problem, a methodology similar to the one used by Wittke (1990) was implemented. In a first stage, a 2D numerical model with plane strain conditions was built with FLAC. Figure 5 shows the grid with the ground topography before and after the excavations of the valley by the river. Opening of the adit in location 2 was also simulated. The grid was more refined close to the river bank in the zone where the tests were performed. This 2D model allowed calculation of the stress components at the measurement points in location 2, but not in location 1, due to the adit orientation at that location. A second numerical model had to be built for this purpose. It is a 100x100 m2 3D model using FLAC3D (Itasca 2006), with a unit width, centred at the adit in location 1. Grid blocks are 0.5x0.5x1 m3 and the approximate shape of the adit is also modelled (Fig. 6). The stresses applied on the boundary

Figure 6. Model (3D) with the adit near location 1.

Figure 7. State of stress along the direction perpendicular to the river around the new powerhouse. 47


A Global Stress Interpretation Model (cont) of this model were the stresses resulting from the application of each of the loading cases Ei in the 2D model. With this 3D model the stress components at the measurement points in location 1 were calculated. Application of this procedure to the tests carried out for the Bemposta II project, gave the following results: k1 = 0.60 k2 = 0.91 and k3 = 0.75. This corresponds to an initial vertical stress nearly equal to the weight of the overburden, and smaller horizontal stresses, 1.5 times lower than the vertical stresses. With these values, it is then possible, to estimate the state of stress at any location in the rock mass, namely around the shaft of the new powerhouse. This is presented in Figure 7, which displays the end result of the global interpretation model.

S13

Salamonde II re-powering scheme S8

The Salamonde II hydroelectric scheme is located on the Rabagão River in the north of Portugal. The re-powering project includes a new hydraulic circuit and a new underground powerhouse. Test measurements for design of the excavations took advantage of the caverns of the existing powerhouse. Six STT overcoring tests were performed from two boreholes: S8 at the ground surface, and S13 at the existing valve chamber (Fig. 8). In each borehole, three tests were performed. The main factor thatJOB affects the: in situ stress distribution TITLE within the rock mass is, in this case, the existence of the old powerhouse cavern.FLAC In this (Version example the5.00) topography of the river valley was not considered of particular relevance. The global interpretation method presented earlier was LEGEND used for calculation of the in situ stresses, with the following additional assumptions: 2-Oct-09 17:06  the rock mass isstep continuous, 12000linearly elastic, homogene3 1.748E+02 ous and isotropic,5.834E+01 with  = 27<x< kN/m ; <y< 2.082E+02  the initial in situ9.176E+01 stress corresponds to the situation before excavation of the existing powerhouse caverns; and Grid plot  plane strain conditions. For interpretation of0the three tests 2Eof1 borehole S13 a 2D mathematical model was used, that represents a cross section of the existing powerhouse caverns. Figure 9 shows the FLAC mesh, where these caverns and borehole S13 are represented. Application of this procedure to the tests carried out in borehole S13 of the Salamonde II project, gave the following results: k1 = 0.90 k2 = 1.43 and k3 = 1.05. The high vertical stresses that were calculated (1.43 times the overburden weight) may be due to the vicinity of the river valley, which was not considered in the model. The horizontal stresses are around 1.5 times lower than the vertical stress.

Figure 8. Layout: Salamonde II re-powering scheme. CONCLUDING REMARKS The in situ stress is a parameter of great importance for the design of underground openings, but it is at the same time very difficult to estimate. This difficulty has to do with several sources of uncertainty that affect its estimation. On one hand, the available measuring devices and methods have their own inherent measuring uncertainties. On the other hand, the measured quantities are often not stresses, but strains, displacements or other quantities. Transformation models that yield stresses based on the measured quantities and on a set of assumptions regarding stress–strain relationships, test geometry and others, also add uncertainty into the stress measurement results. Finally, spatial variability is an unavoidable characteristic of the state of stress in

Figure 9. Mesh detail and location of borehole S13.

r

48 0.700

0.900

1.100 (*10^2)

1.300

1.500


Cornet, F.H. (1993). Stress in rock and rock masses. Comprehensive Rock Engineering, Vol. 3, (Hudson, J., ed.). Pergamon Press, Oxford, pp. 297-327. Fairhurst, C. (2003). Stress estimation in rock: a brief history and review. International Journal of Rock Mechanics and Mining Sciences, Vol. 40, pp. 957-973. Itasca (2005). FLAC, Version 5.0, User‟s Manual. Itasca Consulting Group, Minneapolis, USA, Itasca (2006). FLAC3D, Version 3.1, User‟s Manual. Itasca Consulting Group, Minneapolis, USA. Hudson, J.A., Cornet, F.H. & Christiansson, R. (2003). ISRM Suggested methods for rock stress estimation – Part 1: Strategy for rock stress estimation. Int. Journal of Rock Mechanics and Mining Sciences, Vol. 40, pp. 991-998. Ljunggren, C., Chang, Y., Janson, T. & Christianson, R. (2003). An overview of rock stress measurement methods. Int. Journal of Rock Mechanics and Mining Sciences, Vol. 40, pp. 975-989. LNEC (2006). Tests for the geomechanical characterisation of the rock mass of the new Picote powerhouse (in Portuguese). Report 71/06-NFOS, LNEC, Lisbon. LNEC (2008). Tests for the geomechanical characterisation of the rock mass of the new Bemposta powerhouse (in Portuguese). Report 296/08-NFOS, LNEC, Lisbon. LNEC (2009). Repowering of Salamonde. Overcoring tests for determination of the state of stress (in Portuguese). Report 406/09-NFOS, Lisbon. Pinto, J.L. (1983). Deformability of rock masses (in Portuguese). Research Programme, LNEC, Lisbon. Sousa, L.R., Martins, C.S., & Lamas, L.N. (1986). Development of the techniques of measurement and interpretation of the state of stress in rock masses. Proceedings of the IAEG Int. Congress, Buenos Aires. Wittke, W. (1990). Rock Mechanics: Theory and applications with case histories. Springer-Verlag, Berlin, Heidelberg, New York, Tokyo.

rock masses and corresponds to another major source of uncertainty in the in situ stress estimation. A methodology using a global model that integrates the results of stress measurements obtained by several methods, in different locations, in zones with stress fields that are disturbed by nearby excavations, was presented. This methodology incorporates assumptions regarding the stress field, which may be found reasonable approximations of reality, as well as prior knowledge. Heterogeneity of the rock mass can also be considered. The application examples demonstrate the importance of using a global interpretation model in the averaging of the results of a set of in situ stress measurements. The variability of the stress field and the uncertainties that affect its estimation makes it very hard to interpret individual measurements and, when this is done, the possibility of obtaining erroneous estimates of the stress field is very high. On the contrary, use of a global interpretation model in the application examples that were presented, resulted in the estimation of stress fields that can be directly used for design purposes. The in situ stress testing programme should be prepared having in mind the global interpretation model deemed adequate for each project. The tests should be located in such places that allow one to capture important features of the stress field variation and should also have in mind the numerical model that will be used for the analysis of the results. Sometimes, only long and expensive boreholes are able to reach the rock mass around an underground excavation, and in other cases, depth may make them unfeasible. These difficulties may be overcome by performing additional tests as soon as exploratory or access adits reach the zone of interest, namely using direct measurements such as flat jack tests, and in this way update the the stress field. The number of in situ tests performed during the site characterisation stage to support the design is often very low. This was also the case in the examples presented. As a consequence, it is usually impossible to make any statistical inference about stress variability. Thus, the values of the in situ stresses to be used in design should be carefully defined and it is advisable to use available mean results and to perform judicious sensitivity analysis.

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AKNOWLEDGEMENTS Permission from EDP, Energias de Portugal, S.A. to publish the information regarding the Picote II, Bemposta II and Salamonde II hydroelectric schemes is greatly acknowledged. REFERENCES Amadei, B. & Stephansson, O. (1997) Rock stress and its measurements, Chapman and Hall Publication, London.

Bezalel Haimson explains some of the secrets of hydraulic fracturing at the ISRM In Situ Rock Stress Symposium held in Beijing in 2010.

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The Borehole Wall Stress Relief Method (BWSRM) X.R. Ge, M.X. Hou, China (gexiurun@whrsm.ac.cn ) z

INTRODUCTION In the field of rock mechanics and engineering, the methods to measure the in situ 3D rock stress tensor are mainly of the following two kinds: overcoring stress relief and hydraulic fracturing. The overcoring method can be used to determine the principal values and directions of the in situ 3D rock stress tensor in a single borehole; however, the phenomenon of core breaking occurs easily because of the relatively long rock core sample required in the process of stress relief. Hydraulic fracturing is the most dominant method of in situ rock stress measurement in deep drilled boreholes. The in situ rock stress measurement with hydraulic fracturing is based on the assumption that one of the principal directions of the in situ rock stress tensor is coincident with the borehole axis. This assumption affects the reliability of the stress measuring results to some extent. In order to improve the reliability of rock stress measurement, a new method, the Borehole-Wall Stress Relief Method (BWSRM), to determine the in situ 3D rock stress tensor in a single drilled borehole has been studied in recent years (Ge & Hou, 2004; Ge et al. 2006). Theoretically, the application of this method is free from the limitation of borehole depths and is versatile for any deep borehole. So it perhaps offers an innovative approach to in situ 3D rock stress measurement at great depths.

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In practice, we can arrange three surfaces with different orientations along the length of a drilled borehole wall surface to estimate the local in situ 3D rock stress tensor. The relieved rock core is about 30 mm in diameter, and no less than 36mm in length. With the BWSRM there is no need for a pilot hole along the borehole axis. REFERENCES Ge X R, Hou M X. A new approach to measure geostress: local borehole-wall complete stress relief method. Chinese Journal of Rock Mechanics and Engineering, 2004, 23 (23): 3923-3927 (in Chinese). Ge X R, Hou M X, Wang S L. A new approach for measuring the in situ 3D rock stress tensor in a drilled borehole. In: Proceedings of the International Symposium on In Situ Rock Stress, Trondheim, Norway, 19-21 June 2006, edited by Ming L. et al. London: Taylor & Francis / Balkema, 185-192, 2006.

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PRINCIPLE AND METHOD OF IN SITU 3D ROCK STRESS MEASUREMENT WITH THE BWSRM The determination of the in situ 3D rock stress tensor with BWSRM requires that a relation be derived between the normal strain at a point on the borehole wall surface and the components of the far-field in situ 3D rock stress tensor in the borehole co-ordinate system, Figure 1. If the rock mass is assumed to be continuous, homogeneous, and isotropic, this relation, as mentioned above, can be obtained using the theory of linear elastic rock mechanics. In order to obtain strain measurements with BWSRM, a special stress relief approach is applied here to relieve the rock stresses surrounding the borehole wall. As shown in Figure 2(a), for a given position, a cylindrical rock core sample with a certain length is isolated from the borehole wall along the radial direction through annular cutting techniques by rock core drilling. The stored stresses can be completely relieved when the depth of the rock core sample is deep enough, while the strain responses are monitored by bonding triple-strain gauge rosettes (Fig. 2(a)) on it (Fig. 2 (b)). Thus, three strain measurements can be obtained when the cylindrical core sample is completely relieved. In the same way, one can obtain more strain measurements in the other positions, as shown in Figure 2(b).

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Rockburst Prediction in the Carrara Marble, Italy M. Coli, E. Livi, P. Berry, A. Bandini (Italy), He Manchao, Jia Xuena, China (coli@unifi.it) GEOLOGY AND GEOMECHANICS The Carrara Marble derives from the tectono-metamorphic deformation of an Hettangian (about 200 Ma) carbonate platform. The Carrara Marble is the result of three tertiary (27 to 12 Ma) overprinted tectono-metamorphic deformations onto a massive limestone of carbonate platform origin, Figure 3. Different lithofacies in the platform setting gave rise to the different commercial types of marble. Because of its metamorphic origin and its slight chromatic banding (â&#x20AC;&#x2014;macchiaâ&#x20AC;&#x2DC;), Carrara marble presents a weakly oriented texture which determines a weak anisotropic degree for the mechanical characteristics. In particular, Rotonda (1991) found a degree of anisotropy of about 2% by measuring the P-wave velocities in 36 directions on a spherical specimen (110 mm in diameter). The tectonic action determined a global orthotropic structure and three principal planes of weakness can be recognised in the field. Such planes, at right angles relative to each other and called by quarrymen verso, secondo and contro, control the exploitation and excavation of the Carrara marble, representing planes along which blocks are cut. They sub-divide the rock mass into prismatic blocks, the sizes and shapes of which determine the commercial grade.

INTRODUCTION The exploitation of the world famous Carrara Marble (Tuscany, Italy) (Fig. 1) began with the Romans, decreased in the Middle Ages and increased again during the Renaissance. The production of marble blocks gradually, but slowly, increased up to the end of the 20th century when both the technology and the increment of international assets necessitated evaluation of the amount of marble and to organise its exploitation. In the last twenty years, environmental concerns and mining optimisation induced many quarries to move underground in order to lower the impact on the environment and increase the dimension stone production percentage. At the beginning, many of these underground quarries, due both to cultural heritage and the lack of specific laws, were worked without any geomechanical study, any design, or any bolts or reinforcements, guided only by the instinct and experience of the quarrymen. The present day intense Carrara Marble exploitation, including the widening of the underground quarries into very large sized caverns, new concerns for safety and new specific laws have forced quarriers to apply to designers for upto-date exploitation projects. This study concerns the rockburst problems encountered in the deepest and largest of the Carrara Marble underground quarries: the Carlone quarry.

Note that the Carrara Marble Quarries were the venue for the 1st ISRM Annual Field Trip in 2009, that excursion having been led by Massimo Coli, the lead author of this article.

Figure 2. Geostructural setting of the Carlone quarry area: map and cross-section; marble types: nu = Nuvolato; or = ordinary white; ve = veined; cs = cherty limestone; rv = quarry debris.

Figure 1. The red dot indicates the Carrara Marble district. 51


Rockburst Prediction in the Carrara Marble, Italy (cont) Because fractures are mainly distributed into bands it was possible to categorise the Carrara Marble rock-mass into four rock-mass typologies: intact, scattered fractured, systematically fractured (finimento), intensely fractured (intersection of two finimento), (Coli 1995, Coli 2001a, b, Coli & Livi 2002, Coli et al. 2006). LOCAL SETTING The Carlone quarry is the deepest underground quarry in the Carrara district, it is located in the core of the widest Carrara Marble outcrop (Fig. 2) and crossed by a tunnel of the old marble-railway (built at the end of the XIX century), which, after the II World War, was transformed into a truckway. From the middle of the tunnel, about 500 m below the top of the mountain, the quarry was opened twenty-five years ago, at about 600 m from each tunnel entrance. Nowadays the quarry has been largely widened, and future extensions are planned (Figs. 3 & 4).

Figure 5. Top-heading advancing shaft with traces of rockburst. During excavation works, rockburst events occurred in some panels (Figure 5); as a consequence, those shafts were abandoned and excavation proceeded in different directions. LABORATORY ANALYSIS In order to define the geomechanical behaviour of Carlone quarry‘s marble and to open new insights in the understanding of rockbursts, laboratory analyses were carried out in the laboratories of the Universities of Bologna (Italy) and Beijing (China): in the latter, new equipment was developed for rockburst testing. Physical-mechanical characterisation of intact rock was conducted by the University of Bologna (Italy) according to the ISRM Suggested Methods (ISRM 2007). Samples were cored from a single block along the same direction in order to avoid the influence of anisotropy. 100

Figure 4. Topographic setting of the Carlone quarry: cross section and plan view.

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UCS tests were performed under force-controlled conditions by applying the axial load continuously at a constant stress rate of 0.5 MPa/s until failure occurs. Typical stress– strain curves obtained are shown in Figure 6. This gave a tangent Young‘s modulus of about 49.5 GPa (value measured at 50% of the ultimate UCS) and a Poisson‘s ratio of 0.33. The strength and deformability values were determined on cylindrical specimens with a height to diameter ratio (H/D) of 2 and are comparable to data reported in literature for Carrara marble on samples of the same geometry (Rotonda 1991, Berry & De Virgilio 1985). Franklin and Hoek (1970) obtained a mean value of 92.4 MPa on core specimens of the same diameter and slenderness. Specimens prepared at H/Ds ranging from 0.5 to 3.0 were subjected to uniaxial compression to evaluate the effects of slenderness on strength. Conventional triaxial tests (2 = 3) were conducted in order to study the influence of confining pressure on strength. The tests were carried out at confining stresses of 0, 2, 5, 10, 20 MPa. In Figure 7, the experimental HoekBrown strength curve obtained is compared with HoekBrown curves constructed when processing Carrara marble data reported in the literature (Rotonda 1991, Franklin & Brown 1970).

Figure 8. Test system. conduct a uniaxial or triaxial test. It includes the main machine, the hydraulic pressure controlling system and data acquisition system including force and displacement acquisition, acoustic emission acquisition and high speed digital camera recording. During the test, one surface of the specimen can be unloaded immediately from the true triaxial compression condition, simulating the stress condition for rock mass at the free excavation boundary in underground excavations (He et al. 2010). Test samples were taken from the same block from which core specimens for physical-mechanical characterisation were cored by Bologna University. These samples were generally intact but with some inclined bedding and showed a white colour with grayish veins.  The failure of the marble sample in this study showed a sudden rockburst with violent sound and detachment of rock slabs from the top.  Much more AE energy was released in the rockburst process than that in the initial loading and unloading process, which indicates that dissipated energy would increase with dislocation emission, slipping and shear deformation for the samples corresponding to the formation of transgranular microcracks, while intergranular microcracks would appear under a relatively lower stress state.

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Figure 7. Hoek-Brown strength curves on Carrara marble. ROCKBURST TESTING The true triaxial rock test system (Fig. 8) was developed by Prof. He at China University of Mining & Technology in Beijing. It is a unique system for rockburst testing, which can provide dynamic loading and unloading independently in three principal stress directions, and it can also be used to

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Rockburst Prediction in the Carrara Marble, Italy (cont) FINAL REMARKS There are two types of rockburst, i.e., delayed rockbursts and instantaneous rockbursts. The rockburst that occurred within the Carrara marble laboratory samples belongs to the delayed rockburst type, corresponding to the stress concentration after excavation in the field. The laboratory test shows a critical stress of σmax = 50 MPa for the rockburst of Carrara marble. This result accords quite well with the outcome of the numerical analysis by an FEM (Phase) code, which demonstrated that the vertical stress on the opening side reached about 45 MPa when the first rockburst events occurred in some panels with an embedded depth of 450 m.

sicurezza di cave in galleria nei bacini marmiferi apuani. GEAM, Atti convegno “Le cave in sotterraneo”, Torino 20/6/06, 101-106. E.R.T.A.G. 1980. I Marmi Apuani: schede merceologiche. Firenze: Regione Toscana, Nuova Grafica Fiorentina. Franklin, J.A. & Hoek, E. 1970. Developments in triaxial testing technique. Rock Mechanics, 1970, 2, 223-228. Hawkins, A.B. 1998. Aspects of rock strength. Bull. Eng. Geol. Environ. 57: 17–30. He, M.C., Miao, J.L. &, Feng, J.L. 2010. Rock burst process of limestone and its acoustic emission characteristics under true-triaxial unloading conditions. International Journal of Rock Mechanics & Mining Sciences. 47(2): 286298. Hoek, E. & Brown, E.T. 1980. Underground Excavations in Rock. London: Institution of Mining and Metallurgy. ISRM, R. Ulusay, R. & Hudson, J.A. (Editors) 2007. The Complete ISRM Suggested Methods for Rock Characterization, Testing and Monitoring: 1974-2006. Turkey: ISRM Turkish National Group Ankara. Jaeger, J.C., Cook, N.G.W. & Zimmerman, R.W. 2007. Fundamentals of Rock Mechanics. New York: Wiley. John, M. 1972. The influence of length to diameter ratio on rock properties in uniaxial compression: a contribution to standardization in rock mechanics testing. Rep S Afr CSIR No ME1083/5. Mogi, K. 2007. Experimental rock mechanics. London: Taylor & Francis. Obert, L., Windes, S.L. & Duvall, W.I. 1946. Standardized tests for determining the physical properties of mines rocks. US Bureau of Mines Report of Investigations, 3891, p 1. Rotonda, T. 1991. Mechanical behaviour of an artificially microcracked marble. Proc. 7th Congr. ISRM: 345-350. Rotterdam: Balkema. Tang, C.A., Tham, L.G., Lee, P.K.K. & Liu, H. 2000. Numerical studies of the influence of microstructure on rock failure in uniaxial compression – Part II: constraint, slenderness and size effect. International Journal of Rock Mechanics and Mining Sciences, 37 (4):

ACKNOWLEDGEMENTS We should like to thank Prof. He at China University of Mining & Technology, Beijing, and his colleagues for their contribution to the rockburst tests in the State Key Laboratory for GeoMechanics and Deep Underground Engineering. REFERENCES AND BIBLIOGRAPHY ASTM 1994. American Society for Testing and Materials. Annual book of ASTM standards. Vol 04.08. Philadeplhia, PA, USA. Bandini, A. & Berry, P. 2010. A suggested approach to study variability of impact strength in heterogeneous rock materials. Geoflorida2010 - Advances in analysis, modeling & design. Geotechnical Special Publication, n° 199: 1227-1236. West Palm Beach (FL): 20 – 24 February 2010. Berry, P. & De Virgilio, F. 1985. Significatività dell‘indice di resistenza R.I.H.N. III Convegno Nazionale su Attività Estrattiva di minerali di 2ª categoria, Bari 17-19 gennaio 1985: 103-109. Coli, M. 1995. Geostructural and geomechanical setting of the Carrara Marble quarries, Italy. Mechanics of jointed and faulted rock, MJFR-2, Wien, 10–14 April 1995. Rotterdam: Balkema. Coli, M. 2001a. Geomechanical characterisation of Carrara Marble. ISRM Regional Symposium, EUROCK 2001, Helsinki: 53-57. Rotterdam: Balkema. Coli, M. 2001b. Underground exploitation of the Carrara Marble. In Adachi et al. (eds), Modern Tunneling Science and Technology: 1045-1050. Coli, M. & Livi, E. 2002. Applicazione di tecniche GIS nella pianificazione dell‘attività‘ estrattiva: carte della stabilità generale di versante dei Bacini Marmiferi Industriali del Comune di Carrara. Quarry and Construction 12: 17-25. Coli M., Livi E. & Pini G. (2006) Riferimenti geostrutturali e geomeccanici per una corretta progettazione in

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Present-Day Stress State in South-East Korea C. Chang, T.S. Kang, South Korea INTRODUCTION It is known that structural elements such as active faults and joints influence in situ stress conditions locally (Barton & Zoback 1994, Sassi & Faure 1997, among others). In order to verify the likelihood of a correlation between in situ stress states and regional scale faults in a relatively wide region, we analyse stress tensors in South-Eastern Korea. We use stress data determined through shallow (100–320 m) borehole in situ stress measurements such as the hydraulic fracturing and the overcoring methods. The in situ stress measurement methods provide a complete in situ stress tensor (magnitudes and orientations) at a point. Although the measurements are normally constrained within shallow depths, they are the only methods that can be utilised for stress tensor analysis in a relatively wide region, because of the abundance of data. In order to verify the reliability of the results, we also compare the results with earthquake focal mechanism solutions. The Korean Peninsula is situated near the eastern edge of the Eurasian plate, away from the major plate boundaries, and is typically considered to be tectonically stable. That does not mean that the occurrence of earthquakes is rare. A few tens of weak and intermediate earthquakes take place annually in and adjacent to the Korean Peninsula. Many of these earthquakes may be attributed to intraplate faulting activities triggered by stress accumulation at fault strength. The South-Eastern part of Korea is occupied by a Cretaceous sedimentary basin. Regional scale faults are intensely developed almost all over the area, with their population density varying locally (Fig. 1). Especially noted is a family of densely distributed faults striking to the NNE in the South-Eastern part of the study area. This fault system includes the Yangsan fault, an approximately 200 km long major fault whose contemporary activity has been argued by a number of researchers (Okada et al. 1994, Ree et al. 2003). Evidence, such as fault scarps and slickenlines associated with earthquake events in Quaternary time, has been observed along the Yangsan fault and adjacent area.

plete stress tensors are determined from strain measurements and calculated with knowledge of the elastic constants of the rock. The data were screened, eliminating those with no stress directions and those above 100 m as suggested by Zoback (2007). The majority of selected data are D-quality, and partly C-quality, based on the WSM ranking system. Thus, the data possess quite wide uncertainties. However, several consistent individual D-quality data points in close proximity may reveal meaningful information concerning the stress field, as previous WSM related studies demonstrated (Müller et al. 1992, Zoback 1992, Hillis & Reynolds 2000, Tingay et al. 2010). RESULTS

In situ stress orientations Figure 1 shows the directions of the maximum horizontal stress (SHmax). Overall, the SHmax directions are predominantly ENE–WSW or NE–SW. The SHmax direction is consistent with that estimated using other independent methods such as fault slip analysis (Park et al. 2006) and focal mechanism solutions (shown later). This direction is also

IN SITU STRESS DATA We used in situ stress data collected from the literature (Lim & Lee 1991, Kim 2002, Haimson et al. 2003, Lee & Chang 2007). All these data were determined mostly from hydraulic fracturing stress measurements and partly from overcoring techniques. Typical wireline hydraulic fracturing systems, consisting of a straddle packer assembly pressurised by an hydraulic pump, were used for all the hydraulic fracturing tests. The testing set-up and procedure follow the International Society for Rock Mechanics Suggested Method (Kim & Franklin 1987). The overcoring technique used here utilises a borehole deformation gauge that measures strains in a plane normal to the axis of borehole. Com-

Figure 1. Maximum horizontal principal stress directions in South-Eastern Korea.

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Present-Day Stress State in South-East Korea (cont.) comparable to that in the World Stress Map, which shows an approximately Eâ&#x20AC;&#x201C;W trend of SHmax in this region (Heidbach et al. 2010). A subset of data in the South-Eastern part of the study area shows a systematic bias of the SHmax direction towards the NE or NNE, where NNE-striking sub-parallel fault sets including the Yangsan fault prevail. The SHmax directions determined from these locations are notably parallel to the strike of the fault system. This trend is quite conspicuous since the stress directions away from the fault trend are predominantly ENE. In fact, stress orientations in other regions do not appear to have a clear correlation with the strikes of local faults. Structural controls on the stress field have been investigated by a number of previous studies (e.g. Hudson & Cooling 1988, Evans 1989, Ask 1997, Yale 2003). A common aspect of these studies is that the local stress field can be perturbed by the structural discontinuities represented by faults, such that the maximum stress orientation is diverted parallel or perpendicular to the fault. In particular, Hudson & Cooling (1988) suggested that such a structural control on stress can be attributed to the contrast of the mechanical properties between the surrounding rocks and the faultfilling material. They showed that if the fault-filling material is significantly more compliant than the host rock, stress orientation becomes parallel in the vicinity of the fault. We infer that the local NNE trend of the SHmax direction near the Yangsan fault is suggestive of relatively compliant in-filling material represented by fault gouges and damaged zones with a significant thickness.

Figure 2. Shmin (a, b) and SHmax (c) magnitudes in different locations. Shmin values from locations plotted in (a) are close to, or lower than Sv, and those from locations plotted in (b) are generally higher than Sv. Blue and red circles indicating SHmax in (c) correspond to Shmin plotted in (a) and (b), respectively. To compare stress conditions in different locations visually, we construct in Figure 3 in situ stress contour maps expressed in terms of stress ratios, Kmin (=Shmin/Sv) and Kmax (=SHmax/Sv). Because the SHmax magnitudes depend to some extent on Shmin values, the general trends of both Kmin and Kmax contours are shown to be similar. While the lower values of Kmax (in the middle of the map) are less than 1.4, those in the southern margin reach values as high as ~2.2, demonstrating a clear spatial contrast in stress magnitude.

Comparison with earthquake focal mechanisms Because the in situ stress data represent stress conditions at shallow depths, it is worth comparing them with deeper stress information. A total of 85 contemporary earthquake data with M>1.6 ws used for focal mechanism inversion (following the method given by Gephart (1990)).

In situ stress magnitudes Figure 2 shows the magnitudes of the minimum horizontal principal stresses (Shmin) and maximum horizontal principal stresses (SHmax) in different locations as a function of depth, as well as the vertical stress (Sv, indicated by solid line) calculated from the weight of the overburden (a unit-weight of 26.5 kN/m3 is assumed). The Shmin data overall are notably scattered, as normally expected from the shallow engineering measurements. It is noted that there are slightly different Shmin gradients with depth in different locations. In some locations, the Shmin values are either comparable to or less than Sv (Fig. 2a), while in other locations, these are generally higher than Sv (Fig. 2b). Despite scatter, the SHmax values overall are definitely higher than the vertical stress. Thus, the prevailing stress regime in the region is in favour of reverse faulting and partly strike-slip faulting (Sv ď&#x201A;Ł Shmin < SHmax). The two subsets of SHmax data represented by different symbols are those corresponding to, respectively, relatively lower and higher Shmin data. The difference between these two sub-sets of data is clearer because fundamentally the derivation of SHmax values contains a 3-times amplification of Shmin.

Figure 3. Stress ratio contours: (a) Kmin & (b) Kmax. 56


Hudson, J.A. & Cooling, C.M. 1988. In Situ rock stresses and their measurement in the U.K.-Part I. The current state of knowledge. Int. J. Rock Mech. Min. Sci. & Geomech. Abstr. 25: 363-370. Kim, S.J. 2002. A Study on the Estimation of Design Parameters Appropriate to Korean Rock Masses. Ph.D. Thesis. Daegu: Kyungpook National University. Kim, K. & Franklin, J.A. 1987. Suggested methods for rock stress determination. Int. J. Rock Mech. Min. Sci. & Geomech. Abstr. 24: 59–63. Lee, J.B. & Chang, C. 2007. Current state of stress in southeast Korea. Journal of Engineering Geology 17: 299307. Lim, H.U. & Lee, C.I. 1991. The trends and variations of natural stresses in rock masses with depth. Tunnel and Underground Space 1: 91-101. Moore, D.E. & Lockner, D.A. 2004. Crystallographic controls on the frictional behavior of dry and watersaturated sheet structure minerals. J. Geophys. Res. 109: B03401, 1-16. Morrow, C.A. et al. 2000. The effect of mineral bond strength and adsorbed water on fault gouge frictional strength. Geophysical Research Letters 27: 815-818. Müller, B. et al. 1992. Regional patterns of tectonic stress in Europe. J. Geophys. Res. 97: 11783–11803. Okada, A. et al. 1994. Active fault topography and trench survey in the central part of the Yangsan fault, Southeast Korea. J. Geogr. Japan 103: 111-126. Park, Y. et al. 2006. Fault slip analysis of Quaternary faults in southeastern Korea. Gondwana Research 9: 118-125. Ree, J.H. et al. 2003. Quaternary reactivation of Tertiary faults in the southeastern Korean Peninsula: Age constraint by optically stimulated luminescence dating. Island Arc 12: 1-12. Sassi, W. & Faure, J.-L. 1997. Role of faults and layer interfaces on the spatial variation of stress regimes in basins: inferences from numerical modelling. Tectonophysics 266: 101-119. Tingay, M. et al. 2010. Present-day stress field of Southeast Asia. Tectonophysics 482: 92-104. Yale, D.P. 2003. Fault and stress magnitude controls on variations in the orientation in situ stress. In M. Ameen (ed.) Fracture and In Situ Stress Characterization of Hydrocarbon Reservoirs: 55-64. London: Geological Society. Zoback, M.L. 1992. First- and second-order patterns of stress in the lithosphere: the world stress map project. J. Geophys. Res. 97: 11703-11728. Zoback, M.D. 2007. Reservoir Geomechanics. Cambridge: Cambridge University Press.

The inversion shows that the maximum stress (1) is horizontal and in the direction of ENE, which agree with the shallow in situ stress data. The intermediate and minimum principal stresses (2 and 3) are tilted from the horizontal and vertical directions. A possible reason may be that the two principal stresses may not be clearly resolvable, so that the orientations of these principal stresses can be ‗arbitrary‘. CONCLUSIONS Based on our results, there seems to be a spatial variation of stress orientations and magnitudes. First, there appears to be a systematic tilting of the maximum horizontal stress direction to the strikes of the major fault system. Regarding the stress magnitude, the ratio of horizontal to vertical stress (K) appears to be inversely correlated with the density of regional scale faults; that is, the higher the fault density, the lower the stress magnitude. This relation suggests a likelihood of stress relief due to faulting, which results in a lower stress regime. This is corroborated by stress conditions on the recently activated Quaternary faults that populate the lower K region. The ratios of shear to effective normal stress acting on these fault planes are relatively high; that is, the faults are oriented such that they are stressed at their maximum criticality. Any excess stress may cause slip along the faults, which would result in a release of the regional stress field. REFERENCES AND BIBLIOGRAPHY Ask, M.V.S. 1997. In situ stress from breakouts in the Danish sector of the North Sea. Marine and Petroleum Geology 14: 231-243. Barton, C.A. & Zoback, M.D. 1994. Stress perturbations associated with active faults penetrated by boreholes: Possible evidence for near-complete stress drop and a new technique for stress magnitude measurement. J. Geophys. Res. 99: 9373-9390. Byerlee, J.D. 1978. Friction of rocks. PAGEOPH 116: 615626. Evans, K.F. 1989. Appalachian stress study 3. Regional scale stress variations and their relation to structure and contemporary tectonics. J. Geophys. Res. 94: 1761917645. Gephart, J.W. 1990. FMSI: A Fortran program for inverting fault/slickenside and earthquake focal mechanism data to obtain the regional stress tensor. Comp. Geosci. 16: 953-989. Haimson, B.C. et al. 2003. Shallow hydraulic fracturing measurements in Korea support tectonic and seismic indicators of regional stress. Int. J. Rock Mech. Min. Sci. 40: 1243-1256. Heidbach, O. et al. 2010. Global crustal stress pattern based on the World Stress Map database release 2008. Tectonophysics 482: 3-15. Hillis, R.R. & Reynolds, S.D. 2000. The Australian stress map. J. Geol. Soc. 157: 915-921.

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ISRM Corporate Members 2010 C - CONSULTANTS

All Corporate Members of the ISRM are listed in every Issue of the News Journal, under headings that describe their main activities. If you wish to be listed under another category, or categories, please contact the ISRM Secretariat: (secretariat.isrm@lnec.pt).

3D Geoscience, Inc.; Tokyo, Japan ÅF; Stockholm, Sweden Arcadis Esg; Sèvres, France Basis Soft Inc.; Seoul, Korea Boliden AB; Stockholm, Sweden China Institute of Water Resources and Hydropower Research; Beijing, China China Railway Eryuan Engineering Group Co. Ltd; Sichuan Province, China Chuo Kaihatsu Corporation; Tokyo, Japan Civil Engineering Research & Environmental Studies, Tokyo; Japan Coyne et Bellier; Gennevilliers, France DAELIM Industrial Co., Ltd; Seoul, Korea Dar Al-Handasah Consultants; Cairo, Egipt Dia Consultants Co., Ltd; Tokyo, Japan Docon Co., Ltd; Hokkaido, Japan EDP - Energias de Portugal; Lisbon, Portugal Elletipi S.R.L.; Ferrara, Italy Geomecon GmbH; Potsdam, Germany Geoscience Ltd; Falmouth, UK Geotechnical Engineering Office; Kowloon, Hong Kong. China GMI S.A. Ingenieros Consultores; Lima, Peru Golder Associates; Sweden Golder Associates, Ltd; Burton on Trent; United Kingdom GS Engineering; Seoul, Korea Guangdong Hongda Blasting Engineering Co. Ltd; China Hazama Corporation, Ibaraki, Japan Hokkaido Engineering Consultant Co. Ltd; Hokkaido, Japan Hydrochina Kunming Engineering Corporation; Kun'ming, China Ingenieursozietät Prof. Dr.-Ing. Katzenbach; Frankfurt am Main, Germany Itasca Consulting China Ltd; Hubei Province, China Itasca Consulting Group Inc.; Minneapolis, USA ITOCHU Techno, Solutions Corporation; Tokyo, Japan Kawasaki Geological Engineering; Tokyo, Japan KDC Engineering Co. Ltd; Tokyo, Japan Kiso-Jiban Consultants Co., Ltd; Tokyo, Japan Lahmeyer International Gmbh; Frankfurt am Main, Germany Lehrstuhl für Ingenieurgeologie und Hydrogeologie; Aachen, Germany Lisconcebe - Consultadoria de Projectos de Engenharia, S.A.; Lisbon, Portugal Lombardi Engineering Ltd; Minusio, Switzerland Multiconsult AS; Oslo, Norway Newjec Inc.; Osaka, Japan Nitro Consult AB; Stockholm, Sweden Norwest Holst, Soil Engineering Division; Leeds, UK Prof. Dipl.-Ing. H. Quick; Darmstadt, Germany SAMSUNG Engineering; Seoul, Korea Sanha Engineering & Construction Co.; Kyunggi-do, Korea SEA Consulting s.r.l.; Turino, Italy Shinnikken Consultants Co. Ltd; Tokyo, Japan Solexperts AG; Schwerzenbach, Switzerland SP Technical Research Institute of Sweden, Borås, Sweden Stable Strata Consulting (Pty) Ltd; Mondeor, South Africa Sumiko Consult. Co Ltd; Tokyo, Japan Suncoh Consultants Co. Ltd; Tokyo, Japan Sweco VBB AB, Stockholm, Sweden TESO Engineering Co. Ltd; Seoul, Korea Three Gorges Geotechnical Consultants Co., Ltd; Wuhan, China Tyréns Infrakonsult AB; Sundbyberg, Sweden Vattenfall Power Consultant; Stockholm, Sweden West Japan Engineering Consultant, Inc.; Fukuoka, Japan WSP Finland Ltd; Helsinki, Finland Yachiyo Engineering Co. Ltd; Tokyo, Japan

A - SUPPLIERS OF ROCK MECHANICS EQUIPMENT AND MATERIALS Boliden Mineral; Stockholm, Sweden China Railway 16th Group Co.,Ltd; Beijing, China GCTS Testing Systems; Tempe AZ, USA Geobrugg; Romanshorn, Switzerland Geotechnical Systems Australia Pty Ltd; Bayswater, Australia Glötzl; Rheinstetten, Germany Golder Associates Ltd; Burton on Trent, United Kingdom Interfels; Bad Bentheim, Germany Laboratório Nacional de Engenharia Civil (LNEC); Lisbon, Portugal Oyo Corporation; Tokyo, Japan Sociedade de Explosivos Civis, SA; Lisbon, Portugal Solexperts Ag; Mönchaltorf, Switzerland

B - SUPPLIERS OF ROCK MECHANICS SERVICES Bergab AB; Göteborg, Sweden Boliden Mineral; Stockholm, Sweden China Coal Research Institute; Beijing, China China Railway 16th Group Co.,Ltd; Beijing, China China Railway Eryuan Engineering Group Co. Ltd.; China China Three Gorges University; Hubei Province, China Coyne et Bellier; Gennevilliers, France Dalian Mechsoft Co., Ltd; Lioaning Province, China Elletipi SRL.; Ferrara, Italy Geobrugg; Romanshorn, Switzerland Geomecon GmbH; Potsdam, Germany Geoscience Ltd; Falmouth, UK Golder Associates; Sweden Golder Associates, Ltd; Burton on Trent, United Kingdom Guangdong Hongda Blasting Engineering Co., Ltd; China Huainan Coal Mining (Group) Co. Ltd; China Hydrochina Kunming Engineering Corporation; Kun'ming, China Ingenieursozietät Prof. Dr.-Ing. Katzenbach; Frankfurt am Main, Germany Institute of Rock and Soil Mechanics, The Chinese Academy of Science; China Interfels; Bad Bentheim, Germany Laboratoire Central des Ponts et Chaussées (LCPC); Paris, France Laboratório Nacional de Engenharia Civil (LNEC); Lisbon, Portugal Lehrstuhl für Ingenieurgeologie und Hydrogeologie; Aachen, Germany LEMO, Laboratório de Ensaio de Materiais de Obras, EIM; Oeiras, Portugal Mattest Ltd; Shotts, UK Mesy (I) Pvt. Ltd; Chihat, Lucknow, India Norwest Holst - Soil Engineering Division; Leeds, UK Nottingham Centre for Geomechanics; Nottingham, UK Oyo Corporation; Tokyo, Japan Sanha Engineering & Construction Co.; Kyunggi-do, Korea Shanghai Tunnel Engineering Co., Ltd; China Sociedade de Explosivos Civis, S.A.; Lisbon, Portugal Solexperts Ag Schwerzenbach; Mönchaltorf, Switzerland WSP Finland Ltd; Helsinki, Finland

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SKB; Stockholm, Sweden Solexperts AG; Schwerzenbach, Switzerland SP Technical Research Institute of Sweden; Borås, Sweden

D - CONTRACTORS Besab Betongsprutnings AB; Göteborg, Sweden Cetu Cse Co.; Bron, France China Three Gorges Project Corporation; Yichang, China Eiffage Construction G.D.; Velizy-Villacoublay, France Geoscience Ltd; Falmouth, UK Hazama Corporation; Ibaraki, Japan Immeuble Eurostade, SNCF; La Plaine St. Denis, France Japan Underground Oils; Tokyo, Japan Kajima Corporation; Tokyo, Japan KDC Engineering Co. Ltd; Tokyo, Japan Nishimatsu Construction Co. Ltd; Tokyo, Japan Obayashi Corporation; Tokyo, Japan Shanghai Tunnel Engineering Co. Ltd; China Shimizu Corporation; Tokyo, Japan Skanska AB; Danderyd, Sweden Solexperts AG; Schwerzenbach, Switzerland Taisei Corporation; Tokyo, Japan Tekken Corporation; Tokyo, Japan Tobishima Corporation; Chiba, Japan Toda Corporation; Tokyo, Japan WSP Finland Ltd., Helsinki, Finland

H - GOVERNMENT DEPARTMENTS Geotechnical Engineering Office; Hong Kong, China Institut National de l‘Environment Industriel et des Risques (INERIS); Verneuil en Halatte, France Institute of Rock and Soil Mechanics, The Chinese Academy of Science; China Japan Atomic Energy Agency; Ibaraki, Japan Japan Railway Construction, Transport and Technology Agency; Kanagawa, Japan Laboratório de Engenharia Civil de Macau; Macau, China Laboratório Nacional de Engenharia Civil (LNEC); Lisbon, Portugal LEMO - Laboratório de Ensaio de Materiais de Obras, EIM, Paço de Arcos, Portugal Luleå Tekniska Universitet; Luleå, Sweden Norwegian Public Roads Administration; Oslo, Norway Ordem dos Engenheiros de Angola; Luanda, Angola Royal Institute of Technology - KTH; Stockholm, Sweden SKB; Stockholm, Sweden Skanska AB; Solna, Sweden Universidade de Aveiro - Serviços de Documentação; Aveiro, Portugal

E - ELECTRICITY SUPPLY COMPANIES China Three Gorges Project Corporation; Yichang, China Chugoku Electric Power Co. Inc.; Hiroshima, Japan EDP - Energias de Portugal; Lisbon, Portugal Electric Power Development Co. Ltd; Tokyo, Japan Hokuriku Electric Power Co. Inc.; Fukuoka, Japan Kyushu Electric Power Co Inc.; Fukuoka, Japan Shikoku Electric Power Co.; Kagawa, Japan The Chubu Electric Power Co. Inc.; Nagoya, Japan The Hokkaido Electric Power Co. Inc.; Sopporo, Japan The Kansai Electric Power Co. Inc.; Osaka, Japan The Tokyo Electric Power Co. Inc.; Tokyo, Japan Tohoku Electric Power Co. Inc; Sendai, Japan Tokyo Electric Power Service Co. Ltd; Tokyo, Japan

I - OTHER CORPORATE MEMBERS China Railway Eryuan Engineering Group Co. Ltd; Sichuan Province, China China Three Gorges Project Corporation; Yichang, China Geosigma AB; Uppsala, Sweden Guangdong Hongda Blasting Engineering Co. Ltd; China Immeuble Eurostade – SNCF; La Plaine St. Denis, France ITOCHU Techno – Solutions Corporation; Tokyo, Japan Kokusai Kogyo Co.; Tokyo, Japan Kumagai Gumi Co., Ltd ; Tokyo, Japan Okumura Corporation; Osaka, Japan WSP AB; Stockholm, Sweden

F - MINING COMPANIES Boliden AB; Stockholm, Sweden China Coal Research Institute; Beijing, China CSIR Mining Technology; Auckland Park, South Africa Huainan Coal Mining (Group) Co. Ltd; China LKAB; Luleå, Sweden Nittetsu Mining Co. Ltd; Tokyo, Japan Somincor, Sociedade Mineira de Neves Corvo, S.A.; Castro Verde, Portugal

G - RESEARCH ORGANISATIONS ÅF, Stockholm, Sweden BRGM; Orleans, France Central Research Institute of Electric Power Industry; Chiba, Japan Chalmers Tekniska Högskola; Göteborg, Sweden China Coal Research Institute, China Geoscience Research Laboratory, Co. Ltd; Yamato, Japan Japan Atomic Energy Agency; Ibaraki, Japan Laboratoire Central des Ponts et Chaussées (LCPC); Paris, France Laboratório de Engenharia Civil de Macau; Macau, China Laboratório Nacional de Engenharia Civil (LNEC); Lisbon, Portugal LEMO - Laboratório de Ensaio de Materiais de Obras, EIM, Paço de Arcos, Portugal Norwegian Public Roads Administration; Oslo, Norway Nottingham Centre for Geomechanics; Nottingham, UK Rock Engineering Research - BeFo; Stockholm, Sweden

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Invitation to the 12th ISRM Congress, Beijing, China www.isrm2011.com

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ISRM Newsjournal - 2010, Volume 13