The Singapore Engineer October 2016

The Magazine Of The Institution Of Engineers, Singapore October 2016 MCI (P) 002/03/2016

Celebrating 50 Years of Engineering Excellence

www.ies.org.sg

THE

SINGAPORE ENGINEER COVER STORY: CIVIL & STRUCTURAL ENGINEERING

SKY HABITAT RESOLVES DESIGN CHALLENGES

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CONTENTS Celebrating 50 Years of Engineering Excellence

Founded in 1966

FEATURES 14 CIVIL & STRUCTURAL ENGINEERING: COVER STORY: Sky Habitat resolves design challenges The structural design and construction of the residential building demonstrate high quality and safety.

20 CIVIL & STRUCTURAL ENGINEERING: HDB’s innovations turn water surfaces into green pockets The award-winning ideas help to improve the water quality and promote biodiversity.

26 CONCRETE TECHNOLOGY: Primary concept of the design of prestressed concrete breakwaters against mega-tsunamis Good structural performance makes them a good option for the protection of property.

30 PROJECT APPLICATION: The new Panama Canal The latest generation of concrete admixtures and other chemical products have been used in this major project.

34 TRANSPORTATION ENGINEERING: Malaysia and Singapore sign MOU for the high speed rail project The two countries have given their firm commitment to go ahead.

Chief Editor T Bhaskaran t_b_n8@yahoo.com CEO Angie Ng angie@iesnet.org.sg Publications Manager Desmond Teo desmond@iesnet.org.sg Publications Executive Queek Jiayu jiayu@iesnet.org.sg Media Consultant Roland Ang roland@iesnet.org.sg Published by The Institution of Engineers, Singapore 70 Bukit Tinggi Road Singapore 289758 Tel: 6469 5000 Fax: 6467 1108 Cover designed by Irin Kuah

38 TRANSPORTATION ENGINEERING:

Cover images by CapitaLand Limited

The UK’s Crossrail project is more than 75% complete Construction work on the major infrastructural project is proceeding as scheduled.

42 EDUCATION: UON Singapore celebrates 10th Year Anniversary with Awards and Gala Dinner The wholly owned entity of the University of Newcastle, Australia, continues to expand its programmes in engineering and other areas.

REGULAR SECTIONS 02 MESSAGE 04 INDUSTRY NEWS 12 EVENTS 44 IES UPDATE

The Singapore Engineer is published monthly by The Institution of Engineers, Singapore (IES). The publication is distributed free-of-charge to IES members and affiliates. Views expressed in this publication do not necessarily reflect those of the Editor or IES. All rights reserved. No part of this magazine shall be reproduced, mechanically or electronically, without the prior consent of IES. Whilst every care is taken to ensure accuracy of the content at press time, IES will not be liable for any discrepancies. Unsolicited contributions are welcome but their inclusion in the magazine is at the discretion of the Editor.

Design & layout by 2EZ Asia Pte Ltd Printed in Singapore

October 2016 THE SINGAPORE ENGINEER

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MESSAGE

Increasing productivity in the built environment sector The general outlook for the built environment sector remains progressive. IES reaffirms its support for the government’s efforts in achieving greater productivity across public sector projects.

In a speech made during the Opening of the Singapore Construction Productivity Week 2016 on 18 October 2016, Mr Lawrence Wong, Minister for National Development and Second Minister for Finance, communicated that while there are has been a contraction in private sector projects, the government is committed to roll out more public sector projects for implementation over the next several years and decades. Such projects will be in various areas like housing, estate upgrading, and the construction of new MRT lines as well as other transport facilities. In light of these opportunities, Mr Wong underscored the need for productivity improvements in order to capitalise on the opportunities ahead.

To achieve greater productivity, Mr Wong outlined three of the government’s priorities. The first is encouraging greater upstream collaboration between developers, architects, engineers, and contractors. The next is helping firms harness the full potential of Building Information Modelling (BIM) and Virtual Design and Construction (VDC), to improve collaboration and enhance construction management processes. And finally, helping the industry innovate, so that a future-ready construction sector can be created. This will involve the industry and research institutions to share ideas and work on common research projects in such priority areas as Design for Manufacture and Assembly (DfMA), 3D printing and advanced robotics for construction.

Government-initiated developments certainly point to exciting prospects for engineers and others in the built environment sector. Nevertheless, these government priorities will require a substantial shift in the capabilities of the talent pool across all levels.

In support, IES will do its part by facilitating capacity building through education and training programmes, conferences and seminars. Current and future efforts of the IES are geared towards helping our engineering professionals by creating awareness and promoting better productivity measures so that they may capitalise on all available opportunities.

Er. Chan Ewe Jin Vice President, Infrastructure Cluster

IES Council Members 2016 / 2017 President Er. Edwin Khew Vice Presidents Er. Chan Ewe Jin Mr Mervyn Sirisena Er. Ng Say Cheong Er. Ong See Ho Er. Seow Kang Seng Dr Yeoh Lean Weng Honorary Secretary Dr Boh Jaw Woei Honorary Treasurer Er. Joseph Goh Immediate Past President Er. Chong Kee Sen Past Presidents Prof Chou Siaw Kiang Er. Ho Siong Hin Assistant Honorary Secretary Mr Joseph William Eades Er. Joseph Toh Dr Lim Kok Hwa Assistant Honorary Treasurer Mr Tan Sim Chuan Council Members Prof Chan Eng Soon Dr Chew Soon Hoe Mr Dalson Chung Mr David So Prof Er Meng Joo Mr Goh Yang Miang Ms Jasmine Foo Mr Lee Kwok Weng A/Prof Lee Poh Seng Mr Norman Lee Prof Ramakrishna Seeram Er. Teo Chor Kok Dr Zhou Yi Honorary Council Members Er. Dr Lee Bee Wah Er. Ong Ser Huan Er. Tan Seng Chuan

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INDUSTRY NEWS

Johnson Controls and Tyco complete merger A newly-formed Johnson Controls has begun operations following the successful completion of its merger with Tyco, marking a historic turning point for both companies.

The union of two front-runners in their respective industries brings together best-in-class product, technology and service capabilities across controls, fire, security, HVAC and energy storage.

The new company, with $30 billion in revenue and 117,000 employees, serves the full spectrum of end markets including large institutions, government, commercial buildings, retail, industrial, small business and residential.

Furthermore, Tyco and Johnson Controls’ buildings platforms will be able to create immediate opportunities for growth through cross-selling, complementary branch and distribution channel networks, and expanded global reach for established businesses.

In the longer term, the company is uniquely positioned to drive new innovations in technology and business models to support the smart buildings, campuses and cities of the future as well as building upon strategic, high

Pro Forma for Merger Automotive centric portfolio

Focused multiindustrial with auto business

Power Adient Spin

Fire & Security

Diversified Holding Company

Streamlined operating company

HVAC & Controls

~$49B revenue

Pro Forma After Adient Separation

Power HVAC & Controls Fire & Security

~$32bn revenue

The combined entity after the merger. Source: Johnson Controls and Tyco Merger – Investor Presentation, January 25, 2016.

value-added services driven by data analytics and connectivity like the Retail Solutions and Connected Services businesses.

Johnson Controls will also have one of the largest energy storage platforms with capabilities spanning the technology spectrum to serve an expanding global energy storage market.

“We are more than just two businesses that have come together – we are now one team uniquely positioned to create value,” said Mr Alex

Molinaroli, Johnson Controls chairman and CEO. “Our combined insights and world class technologies will help build even smarter, more secure and more sustainable environments that help our customers win and broadly move the world forward.”

As a result of the robust integration planning already in place, the company is on track to realise US$1 billion of savings related to previously announced merger synergies and productivity initiatives.

NI introduces second-generation vector signal transceiver National Instruments (NI), a provider of platform-based systems that enable engineers and scientists to solve engineering challenges, recently announced a second-generation vector signal transceiver (VST). The NI PXIe5840 module is said to be the world’s first 1 GHz bandwidth VST and is designed to solve challenging RF design and test applications.

NI introduced what is said to be the industry’s first VST with an FPGA programmable by LabVIEW to accel-

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erate the pace of design and lower the cost of test. The second-generation VST demonstrates NI’s continued empowerment of engineers with software-designed instrumentation to stay ahead of the complex and rapidly changing wireless technologies and requirements with innovative RF test, measurement and prototyping solutions.

The NI PXIe-5840 combines a 6.5 GHz RF vector signal generator, 6.5 GHz vector signal analyser, high-

THE SINGAPORE ENGINEER October 2016

performance user-programmable FPGA and high-speed serial and parallel digital interfaces into a single 2-slot PXI Express module. With 1 GHz of bandwidth, the latest VST is suited for a wide range of applications including 802.11ac/ax device testing, mobile/Internet of Things device testing, 5G design and testing, RFIC testing, radar prototyping and more.

To learn more about the secondgeneration VST, visit www.ni.com/vst/.

INDUSTRY NEWS

Enterprise meets technology: More than 300 enabling innovations showcased at TechInnovation The fifth edition of TechnInnovation concluded on 21 September 2016 with a recorded attendance of more than 2,700 par ticipants, an increase of nearly 30 per cent from last year’s turnout. The event also saw 120 exhibitors showcasing more than 300 emerging and ready-to-market technologies.

Held annually, the annual two-day technology marketplace is Singapore’s premier technology brokerage event that brings together international and local technology providers and seekers to explore technology and business collaboration oppor tunities through open innovation.

Organised by IPI, TechInnovation was also an anchor event of the inaugural Singapore Week of Innovation and TeCHnology (SWITCH).

Guest-of-Honour, Deputy Prime Minister Teo Chee Hean, Coordinating Minister for National Security and Chairman of the National Research Foundation delivered the opening address.

This year’s event, themed “Discover, Connect & Collaborate”, saw its unique crowdsourcing segment, crowdpitching sessions and conference tracks focused on the fields of additive manufacturing and Internet-of-Things (IoT) security.

TechInnovation also introduced a brand new segment on EuropeSingapore Par tnership Oppor tunities, giving local enterprises the oppor tunity to expand their reach and connect to Enterprise Europe Network (EEN) par tners from the Czech Republic, France, Germany, Hungary and Spain.

“We saw a strong attendance by delegates and exhibitors … at TechInnovation this year. SMEs accounted for over 70% of the delegate count, and we are especially pleased with the number of technology providers who turned up seeking partnerships and collaborations with the SMEs,” said Professor Lam Khin Yong, Executive Director of IPI. He fur ther added that the commercialisation of the technologies demonstrated at TechInnovation would be mutually beneficial for both providers and SME end-users.

Over 400 business meetings were initiated over two days, with international par ticipants from countries such as Norway, Saudi Arabia, Japan, Korea and Thailand.

Over 70 international speakers presented over two days The conference, which ran in parallel to the exhibition, which saw spir-

ited discussion over trending topics such as additive manufacturing and IoT security. Having addressed a fullhouse session at TechInnovation’s crowdsourcing segment, Mr Wong Wai Meng, CEO of Keppel Data Centres shared, “The excitement and energy can be felt throughout the event and it’s really hear tening to see that our enterprises and people are taking innovation seriously.”

Other speakers, such as Mr Cor t Isernhagen, Managing Director, Asia Pacific at Lux Research, echoed the same sentiment.

“The audience was receptive and we all shared a common goal; finding new applications specifically for IoT and the corresponding security challenges we face. With Singapore’s focus on Smar t Nation technology, the security aspect is especially critical,” he said.

DPM Teo takes a picture of the Robotic Chef, produced by local SME Kurve Automation. He is flanked by Kurve’s director Mr Hui Wing Feh (left) and IPI Executive Director Prof Lam (right).The Robotic Chef a programmble, automated cooking system that can help F&B enterprises increase productivity and improve food production consistency in a cost-effective manner.

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INDUSTRY NEWS

Singapore Power Centre of Excellence commences collaborations with five industry partners Singapore Power Centre of Excellence (SP CoE), a Singapore Power initiative supported by the Economic Development Board, commenced collaborations with five industry players to drive research and development of next-generation energy network technologies.

The partners and projects are: • 3M (Grid Sensing) • GE’s Grid Solutions business (Substation Digitalisation) • IJENKO (Smart Energy Management Platform) • NEC and Space-Time Insight (Energy Network Health Analytics) • OMNETRIC Group (Big Data Analytics) These collaborations, which will draw approximately S$10 million, are part of the CoE’s flagship Singapore Power Energy Advanced Research and Development (SPEAR) pro-

gramme.This amounts to one-third of the overall S$30 million programme which was launched in April 2015 to promote the development, piloting and integration of cutting-edge solutions and technologies in Singapore’s energy infrastructure network.

When completed by 2021, the projects are expected to strengthen the resilience, reliability and efficiency of Singapore’s energy network, thereby supporting SP’s objective to build a future-ready network to enhance the economy and the quality of life.

Projects such as Grid Sensing and Energy Network Health Analytics will provide cutting-edge monitoring systems, predictive alerts and risk assessment analysis through accurate real-time alerts.These will allow SP to further enhance the electricity supply reliability and reduce electrical disruptions to customers by anticipating

and solving network incidents before they occur.

While strengthening the capabilities of the grid currently, the Substation Digitalisation project will deliver sustainable benefits. When implemented, this will relieve network constraints by accelerating renewable connections, providing customers with a greater choice in distributed energy sources (ie renewable energy) when connected to the network.

The Smart Energy Management Platform and Big Data Analytics projects will pilot applications that enable SP to analyse data to gain customer insights, thus enhancing the understanding of end-user behaviour, in order to develop solutions that will help SP better engage its customers during service provision and help them better manage their energy consumption.

Representatives from the various partners pose for a group photo at the SPEAR commencement event. From left: 3M Singapore MD Arthur Fong; GE Grid Solutions President (APAC) Jack Wen; IJENKO CEO Serge Subiron; SP CoE Head Brandon Chia; EDB Cleantech Executive Director Goh Chee Kiong; NEC APAC Smart Energy Division Director Eji Naka; Space-Time Insight Solution Engineer Rochit Sen and OMNETRIC’s Head of Energy Insight (EMEA) Franz Winterauer.

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INDUSTRY NEWS

NYP beefs up campus security with Smart Security Patrol Monitoring System Nanyang Polytechnic (NYP) is beefing up campus security with the upcoming roll out of an advanced smart security patrol monitoring system, which will help in further ensuring a safe and secure environment for staff and students.

Currently undergoing a trial period, the proprietary system uses Geographic Information System (GIS) technology and the campus’ internet Wi-Fi infrastructure to monitor the location of up to 14 guards assigned across 21 blocks, covering 3.5 hectares - or 60 football fields.

Mr Tan Tsu Soo, NYP’s Assistant Manager for the School of Engineering, explained that the system was de-

veloped to equip the security supervisor with the capability to manage and monitor all patrol guards visually over a web-browser in real-time.

“The school’s Wi-Fi access points are constantly transmitting signals which can be easily tracked with a mobile phone app we developed.The app will then transmit (the guards’) position to the system server and visualise the data onto a dynamic mapping platform, allowing the security supervisor to see their location in real-time, and be aware of any adverse events,” he said.

According to Mr Tan, the system will notify the supervisor should a guard

remain stationary for more than 15 minutes. Furthermore, it also provides alerts should a guard deviate from their assigned route by 50 metres.

Though the system is still on trial, NYP’s estate management team and its security provider are interested to have the system put into service by the end of year as part of their consistent efforts to improve efficiency and cost effectiveness. Stakeholder feedback would be included during the development process.

The system was demonstrated at the Esri Singapore User Conference on 27 September 2016, held at Singapore Expo.

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INDUSTRY NEWS

Singapore’s Asiagroup gets region’s first Grove GMK5250L The first Grove GMK5250L all-terrain crane in Singapore has arrived as part of Asiagroup Leasing Pte., Ltd.’s latest deliveries. The heavy lifting and haulage solutions company has ordered nine new cranes from Manitowoc over the past two years.

The arrival of Singapore’s first GMK5250L was commemorated at a special handover event this September at the Manitowoc facility in Tuas, with leadership from both Asiagroup and Manitowoc in attendance.

Mr Teo Yew Boon, Manitowoc’s sales director for mobile and crawler cranes in Asia-Pacific, paid tribute to the ongoing vision of Asiagroup Leasing and said the GMK5250L is a perfect fit for the company.

“Asiagroup Leasing is one of the most forward-thinking crane rental companies in this region and it’s no surprise to see them taking Asia’s first GMK5250L,” he said.

“The company has been constantly investing in the industry’s most advanced lifting equipment so it can provide better service and better solutions to its customers, and based on this philosophy the GMK5250L is a natural addition for them.”

Introduced last year, the GMK5250L has a huge 70m main boom, second only in the Grove lineup to the 80m available on the Grove GMK6300L – which Asiagroup Leasing already owns three of.

“Having such a long boom is a real advantage for the GMK5250L. The longer boom means it can work on bigger developments, while its smaller footprint makes it versatile enough to fit a wide variety of projects,” said Mr Jeffrey Poh, business development manager at Asiagroup Leasing.

He also pointed out that its smaller footprint, compared to other similarly-classed cranes, made it more manoeuvrable optimal for travel on Singapore’s roads.

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After-sales support Asiagroup Leasing plans to deploy the GMK5250L on oil and gas projects, and for work erecting and dismantling tower cranes. In addition to the crane’s excellent manoeuvrability and superior lifting ability, it is also the only mobile crane to feature a VIAB turbo clutch, which offers several benefits, including wear-free starting and braking, and reduced fuel consumption.

The latest deliveries to Asiagroup Leasing boosts the number of Manitowoc cranes in the company’s fleet. In addition to Grove all-terrain cranes, the

THE SINGAPORE ENGINEER October 2016

company also operates several 85001 and 11000-1 Manitowoc crawler cranes in Malaysia and Myanmar.

“We find the cranes from Manitowoc are well-suited to the Singapore market, offer reliable performance and are backed up with excellent after-sales support,” said Mr Poh. Asiagroup Leasing is one of the largest crane rental companies in the South East Asia region. While the company’s headquarters are in Singapore, it also operates crane supply businesses in Malaysia and Myanmar.

The first Grove GMK5250L in Asia.

INDUSTRY NEWS

NTU’s new inspection robot to be tested in JTC’s industrial developments New buildings in Singapore may soon have a high-tech building inspector rolling up to their door steps armed with laser scanners and high-tech cameras that can spot the tiniest cracks and defects.

This new building inspector is a robot invented by scientists from Nanyang Technological University (NTU), together with national industrial developer JTC and local start-up CtrlWorks.

Named QuicaBot – short for Quality Inspection and Assessment Robot – it can move autonomously to scan a room in about half the time taken for manual inspection, using high-tech cameras and laser scanners to pick up building defects like cracks and uneven surfaces.

The robots, which are capable of working in teams, can upload 3D data of their scans to the cloud and inform the human operator, who can then inspect critical and complex defects.

The new robot was developed in one year at the NTU Robotic Research Centre, and is supported by the National Research Foundation, under its Test-Bedding and Demonstration of Innovative Research funding initiative.

The initiative provides funding to facilitate the public sector’s development and deployment of technologies that have the potential to enhance service delivery.

Project leader Assistant Professor Erdal Kayacan, from NTU’s School of Mechanical and Aerospace Engineering, said their key aim is to automate and speed up the building inspection process according to standards set by the Building & Construction Authority.

“Visual inspection of a new building is an intensive effort that takes two inspectors, so we have designed a robot to assist a human inspector to do his job in about half the time, saving precious time and manpower, and

with great accuracy and consistency,” explained Prof Kayacan.

“The robot can scan an entire room to detect defects according to stringent and consistent standards, and then upload its data in 3D into a database. This means all defects will have their visual and detailed measurements recorded automatically, which can be accessed by the inspectors and the building owners.”

Mr Koh Chwee, Director, Technical Services Division of JTC and Co-Director of the NTU-JTC Industrial Infrastructure Innovation Centre (I3C), said that through collaborations with academic institutions like NTU on innovative technologies, JTC hopes to enhance construction productivity for industrial infrastructure projects.

Quick fault-finding robot Common building defects include cracks on walls and ceilings, unevenness in the floor and walls, hollow tiles, and walls that may not be exactly square (i.e. not set at a 90-degree angle).

To detect them manually, a building inspector will have measurement tools like a spirit level and set square.

Tackling the same challenges with higher accuracy, the QuicaBot, which can operate for three days with two

hours of charging, also has its own arsenal of high tech tools. They include: 1) small laser scanner for navigation and mapping 2) large laser scanner to inspect walls evenness and squareness 3) Inclinometer to check evenness of the floor 4) thermal infrared camera to check for hollowness in tiles 5) small standard colour camera to detect cracks on walls To enable quick and nimble movements around the room, the team worked with CtrlWorks to develop the robot’s mobile platform.

Professor Chen I-Ming, Director of the NTU Robotic Research Centre and co-leader of the project, said the robot has already done well in simulated environments.

“Using cameras and lasers which are more accurate than manual measurements, our robot has shown that it is able to assess the interior architectural defects of a building according to existing industry standards,” said Prof Chen.

For the next phase of development, QuicaBot will be test-bedded at suitable locations within JTC’s industrial developments like JTC Space @ Gul, supported by the NTU-JTC I3C.

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INDUSTRY NEWS

Global Alliance Of Cleaning Associations Formed At CESS 2016

Signatories and witnesses of the EMAS MOU for the Global Alliance of Cleaning Associations. From left: Mr Noruddin Haji Idris, President, MACC; Dipl. Kfm.Tommy Gunawan Hardjana, General Secretary, APKLINDO; Mr Elvis Chan, Chairperson, ECMA; Mr Ronnie Tay, CEO, NEA; Dr Amy Khor, Senior Minister of State for the Environment and Water Resources and Advisor for EMAS; Mr Clive Damonze, President, NCCA; Mr Milton Ng, President, EMAS; and Ms Maria Bochkovskaya, Director, ARUK. Image: NEA.

At the CleanEnviro Summit Singapore 2016 in July, the Environmental Management Association of Singapore (EMAS) signed a Memorandum of Understanding (MOU) with five countries to form a Global Alliance of Cleaning Associations.

The aim of the alliance is to encourage the cleaning industry to collaborate, explore business opportunities, export services and products, and share best practices and knowledge.

The other associations on board this alliance are: Environmental Contractors Management Association (ECMA) Hong Kong, Asosiasi Perusahaan Klining Servis Indonesia (APKLINDO), Malaysian Association of Cleaning Contractors (MACC), Russian Cleaning Company Association (ARUK) and National Contract Cleaners Association of South Africa (NCCA).

The signing ceremony was witnessed by Dr Amy Khor, Senior Minister of State for the Environment and Water Resources in her capacity as Advisor for EMAS, and Mr Ronnie Tay, Chief Executive Officer of the National Environment Agency (NEA).

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The agreement was signed by Mr Elvis Chan, Chairperson, ECMA; Dipl. Kfm. Tommy Gunawan Hardjana, General Secretary, APKLINDO; Mr Noruddin Haji Idris, President, MACC; Ms Maria Bochkovskaya, Director, ARUK; Mr Milton Ng, President, EMAS; and Mr Clive Damonze, President, NCCA. The global alliance will serve as a platform for EMAS to extend professional and social links with the respective cleaning associations, and to unify and strengthen the representation of the cleaning industry through collaboration in the following areas: • Exploration of business opportunities and environmental projects; • Joint cleaning industry-related activities such as conferences, symposia, seminars, technical talks, courses, networking sessions and site visits; • Sharing of association news, initiatives or innovative products or services; and • Promoting best practices to improve cleaning operations such as productivity and standards, training methodologies and technology adoption.

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EMAS had mooted the idea of a Global Alliance of Cleaning Associations, and subsequently secured the participation of the regional cleaning associations. NEA had supported the formation of the alliance, and introduced the Russian and South African cleaning associations to EMAS Other MOUs On the same day, EMAS also signed MOUs with the International Facility Management Association (IFMA) Singapore Chapter and Training Masters Workforce Institute Pte Ltd. These MOUs will pave the way for uplifting the cleaning and facility management industry through collaborations and skills upgrading.

President for EMAS, Mr Milton Ng, said, “I am confident that these partnerships will enable EMAS to provide knowledge and technical expertise for our valued members, as we adopt the best practices of other countries and tailor them for the local context.

Together with the Government, service buyers and the union, we will be able to continue to uplift the cleaning industry’s professionalism, standards and productivity.”

EVENTS

Exhibitor response to bauma China 2016 suggests cautious optimism The eighth edition of bauma China will be staged at the Shanghai New International Expo Centre (SNIEC), Shanghai, China, from 22 to 25 November 2016. The international trade fair is a focal point for new products and what is currently in demand in the construction machinery, building material machines, mining machines, construction vehicles and construction equipment fields.

Although the Chinese construction industry is going through a tough period, the figures for bauma China 2016 are positive, with 2,810 exhibitors having registered as of 19 September 2016. The trade fair will again occupy the entire SNIEC site, namely a total of 300,000 m2.

construction of 20 million residential units in urban areas - which will be a boost to the suppliers of equipment, materials and solutions.

Funding programmes for sponge cities Yet another idea for upgrading the infrastructure of smaller and medium-sized Chinese cities, in particular, is the concept of ‘sponge cities’.

As reported by GTAI, communities threatened by water shortages or flooding are to become so-called ‘sponges’ in which 70% of the rainwater is to be captured by modern sewage systems and reused. A funding programme set up by the Chi-

nese central government in 2015 is providing the pilot projects with around 5.9 billion RMB, or around 792 million euros, of support for the period 2016 to 2018.

Forecasts indicate possible revival of growth Driven by the development of new applications such as these and by the replacement of obsolete machinery fleets, the Off-Road Research experts consider it possible that the Chinese construction machinery market could return to growth after 2017, which is good news for companies showcasing their products and innovations at bauma China 2016.

Slight upward trend for asphalt pavers Whereas machinery sales in China in almost all construction machinery product sectors were significantly down, Off-Highway Research identified a slight year-on-year increase in sales of asphalt pavers, of 4%. The reason for this is the persistently high investment by the People’s Republic in infrastructure development. For example, in 2015 alone, 11,000 km of new highways were built.

Stable figures for compact loaders According to Off-Highway Research, sales of compact loaders also proved to be very stable, with only a minor drop. Generally, the British analysts see good long-term prospects for smaller, more technically sophisticated machines. The backdrop to this is the increasing environmental awareness in China, on the one hand, and the imperative of solving new tasks in the technically most optimal way possible, on the other.

Building construction and renovation China’s 13th Five Year Plan (2016 to 2020) envisages the renovation or

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The previous edition of bauma China was held in 2014. Images by Messe München GmbH.

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EVENTS

Impressive attendance at bauma 2016 bauma 2016, the 31st edition of the leading trade fair for Construction Machinery, Building Material Machines, Mining Machines, Construction Vehicles and Construction Equipment, was held in Munich, Germany, from 11 to 17 April 2016.

Organised by Messe München, the event attracted around 580,000 visitors from 200 countries, representing a rise of 9% over the attendance at the previous edition, held in 2013.

A total of 3,423 exhibitors from 58 countries presented their products, developments and innovations on a record 605,000 m2 of exhibition space.

The next edition of the event will be held from 8 to 14 April 2019, in Munich.

A view of the large crowds at bauma 2016. Image by Messe München GmbH.

Messe München enters into partnership with InnoCentive At bauma 2016, Messe München announced a new partnership.

In future, the global innovation pioneer InnoCentive will power Messe München’s Open Innovation service. Companies will benefit from InnoCentive’s Challenge Driven Innovation methodology and have access to even broader expert knowledge, especially when tackling highly complex innovation problems in the construction machinery sector.

On the Innovation Day during the bauma Forum, Stefan Rummel, Managing Director of Messe München GmbH, and Steven Drew,Vice President Business Development EMEA at InnoCentive Inc officially announced the partnership between the two companies. As a result, companies wanting to use the Open Innovation

service can now take advantage of not only the Messe München network, including its trade fairs, but also the InnoCentive global network with over 375,000 creative and diverse minds to solve innovation problems as well as InnoCentive’s Challenge Driven Innovation methodology.

Messe München’s Open Innovation service will leverage InnoCentive’s Challenge Driven Innovation methodology to translate a company’s innovation problems into ‘challenges’ which can then be addressed and solved by the network of problem solvers.

The problem solvers’ work when coming up with a solution is totally anonymous and results are returned straight to the provider of a challenge, in other words, the original company or exhibitor.The

company can then select the best solution and award prize money.

Network members are spread across the world with specialist knowledge in an extremely wide range of areas, acquired through training and represent different types of organisations including research institutions and universities.

Messe München's trade show portfolio includes bauma in Munich and bauma China in Shanghai. It also cooperates with the Association of Equipment Manufacturers (AEM) in the organisation of BAUMA CONEXPO INDIA in Gurgaon/Delhi and BAUMA CONEXPO AFRICA in Johannesburg, South Africa. In December 2015, Messe München expanded its portfolio again, by purchasing the Russian construction-machinery exhibition CTT.

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COVER STORY

Sky Habitat resolves design challenges The project won a DESIGN AND ENGINEERING SAFETY EXCELLENCE AWARD, in the RESIDENTIAL CATEGORY, at BCA AWARDS 2016.

INTRODUCTION Located over a site area of 11,997.10 m2, within walking distance to Bishan MRT Station and Junction 8 mall, Sky Habitat comprises two 38-storey blocks that accommodate 509 residential units. The development also features sky bridges at Levels 14, 26 and 38; an Environmental Deck (Edeck) on the 1st storey; and two basements of carparks.

The design of the building was governed by a height constraint of 140 m AMSL (Above Mean Sea Level). All structures and fixtures above the roof top including TV antenna, obstruction lights, water tanks, lift motor rooms, maintenance equipment, lightning conductors, construction equipment as well as temporary structures like tower crane, were subjected to the same height limit.

SAFETY IN STRUCTURAL DESIGN PROCESS AND SOLUTIONS Splayed shear walls Structurally, one of the challenges in this project was to analyse the stability of three major pairs of splayed walls of Block 7 (North Tower), which slope from Basement 2 to Level 14, as well as the design and structural detailing process. This is not a design that is commonly seen in any normal single block building. Therefore, suitable and valid assumptions and theories were considered carefully prior to the specific analysis and design process.

The featured terracing units at the North Tower are laterally profiled and shaped vertically up along the splayed shear walls which give the overall rigidity of the structures. The shear walls are rigidly tied and connected at the Basement 2 floor diaphragm and Level 14, and are designed taking into account the tensile and compressive

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Sky Habitat features a three-dimensional matrix of homes with private terraces and common gardens, bringing about skyrise greenery and stunning views of the skyline. Image by CapitaLand Limited.

forces, so that the load paths can be closely looped. The three major pairs of splayed shear walls, aligned upwards to Level 14, support the structural steel trusses that transfer the loads from the upper stack of terrace units down to the shear walls.

After viewing the valid analysis theory, the effective wall dimensions and critical load paths were determined, in order to provide a clear and clean load path for the load to transfer down to the foundation, safely.

Therefore, several discussions were held with all the relevant parties to ensure there were no structural openings or any items that would obstruct the transfer load paths.

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Structurally, one of the challenges in this project was to analyse the stability of three major pair of splayed walls of Block 7 (North Tower), which slope from Basement 2 to Level 14.

COVER STORY Sky bridges Another structural challenge encountered was the material selection for the sky bridges, besides analysis.

Selection of the appropriate building materials, based on the different conditions and situations, is one of the responsibilities as a Professional Engineer, because it is as important as performing the analysis and designing, to ensure building safety.

During discussions on this project, a few options were reviewed and explored including, with the assistance of a prestressed concrete specialist, the use of prestressed concrete beams and also prestressed concrete slabs, due to the high cost implications in using structural steel instead of reinforced concrete.

However, structural steel was selected for the sky bridge design, based on several considerations such as overall building behaviour, construction difficulty etc.

It is very hard to cast a long-span structure at such high levels. Even if it can be done, there is still an extremely high risk concerning the safety of the construction workers, not to mention the difficulty in ensuring the quality of the concrete works, which means there is a very high chance that the safety of the structure might be compromised. This is not to say that the construction of the structural steel sky bridge would be easier, but at least the quality of the sky bridge

could be ensured as it is fabricated and inspected on the ground before being hoisted and installed at the elevated level.

Also, using structural steel sky bridges, instead of massive concrete structures, reduces the size of the vertical elements like columns as well as foundation elements. Therefore, structural steel was considered to be more efficient in terms of structural design. Moreover, the sky bridge was intended to be designed as an independent structure, in order to avoid any unwanted resonance effects on the building movement, possibly transferred through the rigid connection with a concrete bridge.

Therefore, structural steel was selected and the support condition of the sky bridge was designed as a pin-roller end condition with a safe allowable range of movement. The three structural steel sky bridges are supported by the towers at Level 14, Level 26 and Level 38.The sky bridges provide the communal links and connectivity for the two groups of residents coming from the North and South Towers. The bridges are delicate, light and sensitive to the structural movement of the two towering structures standing alongside.

The structural design of the bridges and support conditions on the towers were cautiously thought through, bearing in mind the anticipated sway of the towers, simulated by computer

3D structural modelling, and the need to withstand, during their life-span, the most severe or unfavourable load conditions that can be created by a 1 in 100 years wind storm or quake tremors from Sumatra, Indonesia.

QUALITY APPROACH IN DESIGN, DETAILS AND SPECIFICATION Design compliance with local building codes and British Standards First of all, this project was analysed, designed and detailed, based on appropriate local building regulations, codes and standards, as necessary.

The complete set of load combinations was also included in the analysis as well as in the design, by considering every single load case (favourable or unfavourable) to ensure that each of the structural elements was being taken care of thoroughly, without compromising the safety of the building.

Splayed shear walls As mentioned earlier, there are three major pairs of splayed shear walls aligned upwards to Level 14, to support the structural steel trusses that transfer the loads from the upper stack of terrace units down to the shear walls. These three pairs of 500 mm thick splay shear walls were aligned to support the structural transfer trusses at Level 14. Compression tie beams were introduced at Level 14 while tension tie post-tensioned

The structural design of the bridges and support conditions on the towers were cautiously thought through.

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COVER STORY The Sky Habitat basement is surrounded by a series of tightly-knit Contiguous Bored Piles (CBPs) and skin walls. The CBPs, each measuring 600 mm in diameter, form the basement perimeter foundation walls. The CBP wall method was chosen, taking into consideration the given twobasement construction and the site constraints, and also because it offers the best and safest solution for controlling ground movement or deformation, during excavation, while the skin walls were introduced in order to manage the groundwater seepage.

Compression tie beams were introduced at Level 14 while tension tie post-tensioned beams were introduced at Basement 2 to make sure that the load paths are closely looped effectively.

beams were introduced at Basement 2 to make sure that the load paths are closely looped effectively. The correct detailing of the splay shear walls was necessary as they play an important role in transferring down the load safely. The reinforcement for the splay shear wall was designed, based on the forces obtained from 3-D modelling, using ETABS software, and detailed in the proper way so that it was able to achieve the mentioned design intent.

Other than supporting the gravity loading, the splay shear walls were designed to provide stability to the overall building as well as to the lift core walls and staircase storey shelters. A 700 mm thick floor slab acts as a diaphragm to distribute the lateral forces to the splay shear walls and core walls effectively, to provide overall building stability.

Lateral resisting system The overall lateral stability of the building is provided by the central core walls, staircase storey shelters and also the splay shear walls. The building stability was analysed with the 3-D modelling software, ETABS. The inter-storey drift and overall building displacement were controlled to within 1/500, as per the building code statement.

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The mode shape of the building was considered, where its movement in mode 1 and mode 2 is translational while that in mode 3 is rotational. The effective orientation of the lateral resisting system provides high stiffness to the building, ensuring low natural frequency of the building and, in turn, the comfort of the occupants, even at the highest level.

Foundation system The building is supported by a total of 470 bored piles, of 800 mm, 1000 mm, 1200 mm, 1350 mm and 1500 mm diameter, that are cast deep under the building. Out of this total, there are 184 tension piles that have been installed to resist the hydrostatic uplift stresses below the podium area, where there is too little building mass to suppress the floating forces generated by underground water pressure.

3D modelling software was used for transfer truss design.

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Substructure The lowest floor framing, at the B2 level, consists of a conventional castin-situ reinforced concrete flat slab, with a uniform thickness of 500 mm, supported by pilecaps of various sizes.

The 500 mm thick slab is designed to overcome the large amount of hydrostatic uplift stresses existing underneath the lowest structures. Integrally waterproofed concrete was used at the B2 slab to prevent underground water seepage or migration through the sectional thickness. The B1 slab thickness is generally 250 mm, with pockets of 150 mm, 200 mm and 275 mm thicknesses, catering for various floor framing for different needs.

Level 14 transfer truss The loading from the upper level was determined by using both the column load take and 3-D modelling software for transfer truss design. The design of the truss elements and connection detail requirements were based on BS5950.

COVER STORY Superstructure The design for the superstructure from Level 15 to the upper roof was easier and quite straight-forward as the building stability and lateral resisting system had been looked into carefully. However, the design and detailing of the superstructure still had to be taken care of, in order to achieve the design intent and to safeguard the building. Orion was used for the subframe design, including conventional reinforced concrete beam and slab as well as the design of the flat plate.

Prokon was used for the design of elements like columns and walls as well as some beams. The reinforcement was provided, based on the required steel area and was detailed effectively as per the building code. In addition, Excel spreadsheets were used for some simple calculations such as for punching shear checking, crack width checking etc.

DESIGN FOR SAFE OPERATION AND MAINTENANCE Inspection of staircase storey shelters Inspections were conducted by an experienced BCA officer on the staircase storey shelters, to ensure that the quality of construction was met and local authority requirements were complied with. Rectification works were carried out to enhance the quality of the staircase storey shelters and to safeguard the building, based on the comments or suggestions made by the officer.

Checking human comfort level Tests were carried out on building acceleration and the results were submitted to BCA, to make sure that the human comfort level under the wind load is acceptable.

CONSTRUCTION QUALITY AND SAFETY Excavation and temporary retaining structure system A combination of ground anchor system, horizontal diagonal struts, raker

The method of installation and removal of ground anchors

struts and temporary earth berm systems was adopted to ensure excavation works were carried out in a safe, controlled and predictable manner, with a good ground instrumentation monitoring system in place.

Removable ground anchors, installed along Bishan Street 14 and Bishan Street 15, together with CBPs served to resist the lateral earth pressure during the basement excavation stage. The ground anchor system helped to keep the construction site free of complex internal steel strutting, so as to expedite the earthwork excavation and substructure construction progress. It also provided a neat and safe construction environment for the workers. Layers of temporary ground anchors were installed at various pre-determined levels and subsequently removed progressively upon the casting of the permanent structural slab.

A diagonal and raker struts system was adopted along the common boundary shared with the undeveloped HDB lot. It is similar to the ground anchor system, with the struts installed top-down at pre-determined levels as the excavation progressed deeper, and then removed and replaced by permanent structures.

Site walks There were site walks, thrice a week, together with all relevant parties including clients and site supervisors, to observe the safety of the site. This helped to improve the site safety, with the respective professionals from the relevant parties offering suggestions

based on their own concerns. Comments and suggestions were given for every unsafe situation observed on site. All site observations were recorded and rectifications or actions were carried out immediately without delay, to prevent the same issue from happening again.

Site meetings There were regular meetings, including technical meetings, held on site, to discuss every single site-related issue, so that urgent issues, that required the professional views from each relevant party, were raised for immediate decisions and actions. Thus, site issues were noticed, highlighted and solved by every party, without delay, and the quality of the construction was guaranteed.

Ground instrumentation monitoring plan There was a ground instrumentation monitoring plan prepared for a better and safer construction. Approximately 152 instruments were installed, including inwall inclinometers, ground water standpipes, vibrating wire piezometers, ground settlement measurement instruments, load cells on ground anchors, strain gauges on steel struts, building settlement markers and tilt meters. The monitoring frequency was three times a week, to obtain more effective results, and monitoring reports were sent for review or comment.

Inspections and testing The concrete mix design was sent for checking and approval, before the

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COVER STORY concrete mix was ready to be manufactured in the factory. This was followed by concrete cube testing. Every batch of concrete delivered to site was inspected by the site supervisor, to make sure the concrete strength and concrete quality achieved the design intent and compliance with the regulations. The inspections were also conducted for the structural steel and the reinforcement bars, so that only high quality materials were used during construction. Inspections were carried out before casting of all structural elements, and remedial actions were taken to guarantee the structural elements were built in accordance with the design drawings.

Sequence for the construction of sky bridges As mentioned earlier, one of the difficulties was the construction of the sky bridges. Several discussions were held with specialists, to ensure a safe and workable construction method.

The sky bridge for Level 38 was fabricated in three main parts, comprising two short-end spans and one middle span.

The two short-end spans were first installed at Level 38, together with the hoisting machine. Then, the middle span was fabricated and inspected on the ground before being hoisted carefully to Level 38 and connected to both end spans by bolting and welding. This was followed by the installation of the sky bridge at level 26 and the sky bridge at level 14, using the same sequence.

Level 1 slab strengthening for prefabricated truss Since the truss section was prefabricated at ground level, as mentioned earlier, the particular slab was strengthened to cater for the additional loading sections during the prefabrication process. Therefore, the slab was designed for a live load = 15 kPa, in order to sustain the construction loading, so that the truss section could be moved to an area between the towers safely before being hoisted

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actions could be taken if there were ‘alert level’ conditions and thus minimise the impacts during construction.

Pest control Pest control is always an important aspect that needs to be considered during construction. The site supervisors and site staff always checked the construction site and actions were taken if there was any water ponding, in order to make sure that there was no sign of mosquito breeding.

A special system was used as temporary support for the splay walls.

up for installation. Furthermore, the slabs at Basement 1 and Basement 2 were strengthened, as well, in order to provide a safe platform for the construction, especially of the temporary support for the splay walls.

Temporary support staging for splay walls Specific temporary support was prepared by a specialist and sent for review and comments.

The splay walls were analysed, using ETABS, and the loading from the splay walls was extracted for temporary support design.

The special support system, Quad Shore, consisting of the Quad Support Body and Quad Support Jack, was provided, together with bracing rods, as the temporary support for the splay walls.

PUBLIC SAFETY Hoardings Although the construction site had no populated neighbourhood, some measures were taken to keep the public safe. One of the measures was providing hoardings which were installed by a registered licensed contractor, in the area surrounding the construction site, to prevent unauthorised people from entering the site, accidentally.

Ground instrumentation plan The monitoring programme allowed relevant parties to supervise and monitor the nearby site conditions, due to the construction activities. Remedial

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Adoption of bored pile system The bored pile system was chosen for the foundation system, instead of driven piles, in order to minimise the noise pollution.

Keeping surrounding site area clean and safe The site supervisors ensured the site area was always clean and free of hazardous materials such as reinforcement steel bars and concrete.

All debris was transported into the appropriate site locations, beyond the reach of the public.

PROJECT CREDITS Qualified Person Er. Lai Huen Poh Civil & Structural Consultant RSP Architects Planners & Engineers (Pte) Ltd (Director-In-Charge Er. Lai Chi Kin) Builder Shimizu Corporation Developer CapitaLand Mitsubishi Estate Asia Pte Ltd Shimizu Investment (Asia) Pte Ltd Design Consultant Safdie Architects, Boston, USA Architectural Consultant DCA Architects Pte Ltd

Images by CapitaLand Limited and RSP Architects Planners & Engineers (Pte) Ltd

CIVIL & STRUCTURAL ENGINEERING

HDB’s innovations turn water surfaces into green pockets For the in-house development of the floating wetlands system and freshwater-tolerant mangroves, and their successful application at MyWaterway@Punggol, the Housing & Development Board (HDB) won the IES Prestigious Engineering Achievement Award 2016, in the Applied Research Category.

GREENING MYWATERWAY@PUNGGOL In 2011, HDB announced the plan to develop Punggol as Singapore’s first eco-town. A holistic and comprehensive Sustainable Development (SD) framework, covering social, economic and environmental considerations, was devised to steer the development of the eco-town. One of the desired SD outcomes is ‘enhanced greenery and biodiversity’.

To achieve this outcome, and since Punggol is also positioned as a 'living laboratory' for testing new urban solutions, the HDB team explored innovative ways to intensify greenery for MyWaterway@Punggol which, at 4.2 km in length, is the nation’s first and longest man-made waterway. It meanders through Punggol eco-town, providing a good base for HDB to test-bed eco-friendly features and sustainability-driven solutions to improve water quality, enhance the riverbank and promote biodiversity.

Accordingly, freshwater-tolerant mangroves and the floating wetlands system were developed, in-house, by HDB’s Building & Research Institute.

Whilst achieving the above objectives, they also serve to transform the waterway into a picturesque landmark of Punggol.

CULTIVATION OF FRESHWATER-TOLERANT MANGROVES

The introduction of freshwater-tolerant mangroves helps to fortify and stabilise the riverbank, by leveraging the natural ability of the roots of these shrubs and trees to bind soil effectively.

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MyWaterway@Punggol is the nation’s first and longest man-made waterway.

Freshwater-tolerant mangroves fortify and stabilise the riverbank.

The carefully cultivated mangroves comprising 35 species, including some endangered ones native to Singapore, were tested and proven to be resilient in the freshwater conditions of the waterway. Today, MyWaterway@ Punggol has become the first and only man-made site in Singapore where visitors can see such a large variety of native freshwater-tolerant

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mangroves.

Once established, the roots of the mangroves will gradually stabilise the slope of the waterway embankments and cleanse the water naturally. The foliage from mangroves has provided some green shade from the tropical weather, reduced ambient temperature and enhanced thermal comfort for visitors and residents of Pung-

CIVIL & STRUCTURAL ENGINEERING gol, as they stroll leisurely along the waterway during daytime. They have transformed MyWaterway@Punggol into an attractive ‘relief corridor’ within a high density urban living environment. Such a corridor will provide the opportunity for outdoor education on the characteristics of mangroves which are an integral part of Singapore’s natural heritage. It also builds up the landscaping industry by increasing the diversity of plants.

Effect of mangroves on slope stability In the geotechnical engineering and design, the HDB team stretched the conventional design approach to adopt unsaturated soil conditions for slope stability analysis. In this project, the team cultivated an arboretum of freshwater-tolerant mangroves along MyWaterway@Punggol. An integrated design approach was adopted, that incorporated both soil engineering principles and organic growth effects of vegetation roots. The latter was seen to not only strengthen embankments and control slope erosion, but also contribute significantly to overall aesthetics along the waterway. Based on its research and development, the team strategically located mangroves (planted across the entire slope face) to improve slope stability in a gradual and cost-effective manner, as these plants maintain and enhance soil suction within the vicinity of their roots.

Under certain soil characteristics and slope profiles, this methodology can replace the installation of geotextile bags and/or the construction of reinforced concrete walls.

The use of Geostudio software such as Slope/W helped to compute the factor of safety for slopes in relation to the mangroves, and enabled simple and complex analyses for a variety of slip surface shapes under different pore-water pressure conditions, soil properties, analysis methods and loading conditions.

Seep/W software was used to analyse groundwater seepage for differ-

Freshwater swamp species of vegetation attract wild butterflies and dragonflies.

ent types of conditions, from simple saturated steady-state to sophisticated saturated/unsaturated timedependent analyses for slopes. This saved engineers time as they did not have to perform conventional calculations.

Improving biodiversity Freshwater-tolerant mangroves and floating wetlands provide important habitats for many species of wild flora and fauna. For greater outcomes, HDB’s in-house engineers and landscape architects jointly planned and designed the freshwater-tolerant mangrove habitats to include different strata or layered vegetation, in order to ensure biodiversity. For example, freshwater swamp species of vegetation, that are 5 m high and shorter, attract wild butterflies and dragonflies, whilst the taller freshwater-tolerant mangrove species draw bird species such as sunbirds and kingfishers.

Such biodiversity levels along Punggol Waterway form part of the sustainable framework that supports a biophilic living environment in Punggol Eco-Town, and bring nature closer to residents. They also support the eco-learning journey for visitors to MyWaterway@Punggol.

DEVELOPMENT OF THE FLOATING WETLANDS SYSTEM There is a need to develop innovative and biological floating wetlands systems best suited for the country’s tropical environment, that also provide lively ecological habitats.

Floating wetlands placed in water bodies can help to improve the water quality in the immediate vicinity through the absorption of nutrients by the roots of the plants. At MyWaterway@Punggol, the floating wetlands also help to soften the hardscape, such as the columns of footbridges and concrete structures, along the waterway.

The floating wetlands system germinated from the idea of intensifying greenery by effectively utilising the large surface area of the waterway.

In designing the floating platforms, HDB’s team of engineers was inspired by the organic form of a honeycomb which is made up of hexagonal cells, bound to one another to create a light-weight structure with high strength and rigidity.

The resulting form for the floating wetlands system has two key design features:

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CIVIL & STRUCTURAL ENGINEERING • It allows wetlands plants to be cultivated in environment-friendly plant media (coconut fibre and woven mat), best suited for the freshwater conditions within MyWaterway@ Punggol, thereby transforming plain water surfaces into pockets of greenery, that beautify the environment, cleanse the water and improve biodiversity. • Through the use of hexagonallyshaped, light-weight modules that can be easily assembled and placed anywhere on the water surface, configurations with different shapes and sizes can be obtained. HDB also invented and patented a unique interlocking system for better rigidity and stability, especially to support maintenance workers standing on the floating modules when maintaining the vegetation. It was also designed to withstand wave action from winds or from passing maintenance boats along the waterway.

The interlocking system comprises protrusions and depressions on each side of the hexagonal floating module. It is further reinforced with stainless steel connector pins for better rigidity and stability of the configured system. This modular system has a short on-site assembling time. It has solid pieces of polyurethane foam implanted in the factory and workers just need to assemble the prefabricated modules to form any shape.

The floating wetlands system is built on hexagonal modules which are connected together with an interlocking system comprising protrusions and depressions on each side of the floating modules which are then reinforced with stainless steel connector pins.These pins are capped with locks, to prevent tampering and vandalism.

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Floating wetlands at the gateway to MyWaterway@Punggol, near Jewel Bridge, help to soften the concrete structures of the bridge.

Wetlands plants are cultivated on the hexagaonal modules.

HDB team members standing on a floating wetlands system.

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CIVIL & STRUCTURAL ENGINEERING To enable the ‘green honeycomb’ to improve water quality in the waterway, a total of 15 wetlands plant species were carefully chosen for their ‘phyto-remediation’ ability (the ability to absorb nutrients like nitrogen and phosphorus and minimise algae growth) and cultivated on the floating wetlands system.

Application of Finite Element Analysis Beyond conventional design, the HDB team collaborated with the National University of Singapore (NUS) to apply numerical analysis, in the development of a floating wetlands system that overcame current limitations of existing systems, in terms of buoyancy, system modularity and loading capacity. In this way, the team achieved better designs for enhanced safety, flexibility in design and increased usage.

Both static and hydroelastic analyses were performed to determine whether the floating module could meet the minimum freeboard, strength and serviceability requirements. Hydroelastic analysis was also carried out to assess the degree of flexibility of the floating wetlands system.

HDB collaborated with NUS to perform Finite Element Analysis (FEA) of the configured wetlands.

Both static and hydroelastic analyses were carried out to determine the deformations and stress distributions in floating wetlands systems.

Under static analysis, different combinations and distributions of various loading conditions were studied. The load cases were: • Case 1: Self-weight • Case 2: Case 1 + plant loads • Case 3: Case 2 + one worker (80 kg) • Case 4: Case 2 + Two workers standing side-by-side • Case 5: Case 2 + Two workers standing 1m apart Under hydroelastic analysis, the configured platforms, subjected to water waves from passing boats or

Different loading patterns and the respective deflections

Different sizes and patterns of floating wetlands subjected to waves from different directions

strong winds, were analysed.

The use of the ABAQUS software shortened the computational time (to hours instead of weeks) to perform numerical FEA, especially when it came to refining the design of floating modules and re-analysing under the static and hydroelastic conditions.

Static analysis For analysis, a 3D finite element model of a floating module was adopted for optimal sizing and thickness validation. The aim was to produce a costeffective design, requiring minimal amount of material.

For example, each module was discretised by a 4-node thick shell element (S4R - shell 4-node reduced integration element) and a 3-node thick shell element (S3R - shell 3-node reduced integration element), for a total of 3,596 elements. Each stainless steel pin (used to interlock adjacent float-

ing modules) was discretised by using twenty-two 8-node brick elements (C3 D8R - continuum 3-dimensional 8-node reduced integration element).

The floating system was also analysed to ascertain the minimum configuration of modules to support human and plant loads, based on 4 columns x 3 rows of modules. This will form part of the guidelines for future projects.

Hydroelastic analysis As the floating wetlands are relatively flexible, they exhibit elastic deformation. This is similar to a pontoon-type, very large floating structure subjected to wave actions. Hence, there is a need to perform hydroelastic analyses to estimate the deformation of the entire structure, when floating wetlands are exposed to wave action caused by boats sailing past or caused by strong winds. The floating structure was modelled as a thick plate and numerical techniques were used

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CIVIL & STRUCTURAL ENGINEERING to solve the fluid-structure interaction problem. The techniques also determined the vibration frequencies and modes as well as the modal stresses and deflections of the floating structure.

Floating wetlands at strategic locations These floating wetlands were introduced at strategic locations along MyWaterway@Punggol, where visitors gather, so that they can be closer to nature. For example, the wetlands have been positioned at the mouth of MyWaterway@Punggol, as a gesture of welcome to kayakists and canoeists entering the waterway. They have also been placed close to the pedestrian bridges and boardwalks, where visitors gather to see the families of otters and birds species at close range, and installed near steps where residents and visitors sit, so that they can enjoy the enhanced views. At the same time, people strolling along the sides of the waterway can experience visually pleasing scenery on both land and water.

HDB consulted extensively with its landscape architects on the choice of resilient wetlands plant species, before test-bedding them at its HDB Centre of Building Research. The selected plants species were then deployed along MyWaterway@Punggol.

NATURAL CLEANSING OF WATER

Apart from eco-drains lining both sides of MyWaterway@Punggol and a string of strategically located aerators, organic urban solutions were also incorporated along the waterway. This is to enhance the water quality. The freshwater-tolerant mangrove species were extensively planted along the waterway to promote phyto-remediation. They also slow down water flows and promote sedimentation, hence reducing turbidity.

Similarly, the emergent plants on floating wetlands also absorb nutrients through their roots.

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Floating wetlands are placed near steps, providing people who are seated with a visually pleasing experience.

To further validate the positive effects of mangroves and floating wetlands on water quality, HDB collaborated with Singapore Polytechnic and Ngee Ann Polytechnic to collect water samples on a monthly basis along MyWaterway@Punggol, and conducted in-situ analyses and laboratory tests.

Data collected showed that over time, water quality did improve. For example, the overall levels of suspended solids in the water, close to the mangroves and floating wetlands, are about 30% lower, while nutrient levels are 20% lower.

Such cleaner water supports a healthier environment for biodiversity to thrive, and minimises the likelihood of widespread algae growth.

SUMMARY Today, more than 35 species of freshwater-tolerant mangroves and floating wetlands with 15 plant species have been placed along the waterway.

The HDB team has, besides enhancing ‘green living by the waters’, also demonstrated the following: • The successful adoption of planting as a natural means to stablise embankments.

• The enhancement of water quality through natural means - with about 20% reduction in total nitrates and

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total phosphates, and a 30% reduction in turbidity levels.

• An increase in the biodiversity, with 92 species of birds, 11 species of butterflies and 17 species of dragonflies flourishing along the waterway.

MOVING FORWARD

The floating structure exerts a light footprint on the environment and is therefore a possible solution when deploying light ‘man-made islands’ on water bodies for recreational activities and amenities. It can be a permanent mobile sanctuary for plants, birds and other wildlife. Its versatile structure could also be used for floating jetties and floating roadways.

HDB is exploring the possibility of using the floating wetlands system in areas beyond greening. One area that is being studied is the use of this system to hold solar panels on water surfaces to tap solar energy. Beyond Punggol, HDB will also explore the possibility of applying these new environmentally sustainable solutions to both existing and upcoming towns and estates, to bring greenery and biodiversity to more residents.

All images by Housing & Development Board

CONCRETE TECHNOLOGY

Primary concept of the design of prestressed concrete breakwaters against mega-tsunamis

by Shoji Ikeda, Professor Emeritus of Yokohama National University, Japan In Japan, the severe mega-tsunami invaded the eastern coasts of the mainland on 11 March 2011. The measured highest height of the tsunami was more than 30 m. The next huge tsunamis are anticipated to happen in the southern part of Japan within two decades, due to the Nankai Trough Earthquake. It would not be logical to construct breakwaters higher than the recorded highest tsunami around the country. Therefore, a basic or primary concept for the design of breakwaters against mega-tsunamis which invade once in several hundred years must necessarily be based on harmonisation between daily life and disaster prevention.

The author developed a primary concept for such a breakwater that protects the society and wealth of the nation. The protection of life must be treated separately from the protection of wealth. This simple concept can be used to construct moderate-height breakwaters where the height can be determined according to the wealth of the society and the desire of the people for their open spaces. Prestressed concrete breakwaters would be the most adequate type of the structure due to its resilient structural performance.

Recent experience of a mega-tsunami There occurred a great earthquake of M9.0 in the eastern part of Japan on 11 March 2011, followed by the mega-tsunami. The duration of the main shock was three minutes, followed by consecutive severe aftershocks. The magnitude of 9.0 was the highest in the history of Japan, so far. The vast regions of eastern Japan were devastated mainly by the mega-tsunami.

About 20,000 people died or were missing although certain precautionary counter-measures were provided.

In addition, after the successful emergency shutdowns were performed, the reactors in Fukushima No 1 Nuclear Power Station went out of control, due to the complete loss of electricity caused by the invasion of the tsunami water into the facility. Eventually, radioactive materials were spread as a result of the destruction of encasing structures due to hydrogen explosions and they contaminated the surrounding areas including Tokyo.

This great disaster was named ‘Great East Japan Earthquake Disaster’.

From these fatal experiences, many important lessons were learned including the following (and urgent

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counter-measures against future hazards were drawn up): • It would be almost impossible, at present, to avoid the damage in conventional cities due to megatsunamis, therefore careful and deliberate counter-measures should urgently be prepared, to protect human lives according to specific local conditions.

• The mega-tsunami occurs once in several hundred years. Therefore, we must review the history of disasters in the specific local areas.

Evidence of past mega-tsunamis could be found by digging the layers of the ground.

• High-rise artificial land should be built up with highly durable concrete structures, as soon as possible, in tsunami anticipated areas.

• Reliable warning systems are essential for the evacuation in case of a tsunami and earthquake.

• Education and exercises are the most effective counter-measures.

• The alert system for emergency train stoppage was successfully ordered in this particular disaster in Japan. Therefore, no derailing was seen during the earthquake.

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• Nuclear power plants should be properly protected against any kind of disturbances such as terrorism, earthquakes and tsunamis, without exception.

• Electricity is essential, next to the air, and atomic energy should be properly controlled.

• Modern life cannot exist without electricity.

On the other hand, great earthquakes would be triggered in nearby regions by the previous one, say, the Great East Japan Earthquake.

Therefore, it is extremely urgent that there is a comprehensive rule or charter for the prevention and mitigation against such great earthquakes and mega-tsunamis by referring to the lessons obtained from our updated experiences.

In Japan, a huge earthquake and tsunami happened in 1498, about 500 years ago, due to the Nankai Trough failure in the central and western coastal areas of Japan, which claimed more than 40,000 lives, mainly by the mega-tsunami. If a similar earthquake and tsunami occurred today in the same areas, the number of fatalities, as predicted, would be 10 times or more, because of the increase in the

CONCRETE TECHNOLOGY population. Therefore, the preparation against such a mega-tsunami in these areas is extremely urgent in Japan right now.

People living in the tsunami-affected area should recognise that they live on the seashore.

At present, four years have passed calmly without any big earthquake and tsunami in Japan. During this period, the author stipulated ‘A rule for prevention and mitigation of great disasters’ [1] and proposed self-rising tsunami facilities [2], [3].

This article presents further scrutinised anti-tsunami deliberations.

Significance of a tsunami facility and prestressed structures The essential matter of the protection against a mega-tsunami is the safety of human lives. However, it would be impossible to guarantee the safety of human lives by solely constructing a high tsunami breakwater, due to the possibility of the occurrence of a tsunami that is higher than the designated tsunami height. On the other hand, people living in the nearby area of the seashore do not want to have a higher breakwater which separates the area from the seashore and disturbs the scenery of the seaside, although the breakwater would protect the society. Therefore, it is quite difficult to determine the most suitable height of the tsunami breakwater.

The main reason for this difficulty can be identified by the fact that the construction of a tsunami breakwater is intended to protect both human lives and the individual and social properties at the same time, although the height of the tsunami cannot be estimated exactly. To overcome this difficulty, a definite breakthrough is required.The author has found such a simple solution for a breakwater that protects the society and wealth of the nation. The protection of life must be treated separately from the protection of properties and the wealth.

This simple concept can promote the construction of moderate-height breakwaters, where the height can be determined according to the wealth of the society and the desire of the people for their open spaces. Prestressed concrete breakwaters would be the most adequate type of structure, due to their resilient structural performance.

The following are the necessary conditions for the success of this concept: a) Life-saving facilities, such as a tsunami-shelter, should be built independently from the construction of the breakwater. b) Each person staying near the seashore should hold any kind of buoyancy, equivalent to air of 4 litres, by carrying, for example, two 2-litre

empty PET bottles, as part of selfresponsibility against mega-tsunamis. c) The design height of the specific tsunami breakwater should be determined according to the costeffectiveness of the construction of the breakwater, based on the predicted economic loss in case of overflowing of the tsunami water. d) The designated tsunami breakwater should be strong enough to resist severe earthquake forces and the overflowing of tsunami water. e) Durable prestressed concrete structures are highly recommended for the breakwater, due to the inherent resilient performance of the structures. Individually epoxycoated strands for prestressing should be used to facilitate highly durable, say, more than 100 years durability, structures. f) Ground anchors with prestressing cables should be adopted against buoyancy and instability of the breakwater.

Table 1 shows the response to occurrence of the tsunami of 100 years return period on human life, property and wealth, and the infrastructure. For instance, a breakwater designed for 50 years return period of the tsunami cannot protect the property, wealth and the infrastructure, as shown in Case 3 in Table 1.

Countermeasure

Human Life

Property & Wealth

Infrastructure

1

As Natural

Serious Condition, Self-Responsibility

Fatally Suffered, Self-Responsibility

Fatally Suffered

2

High Tide Dike (10 Years R.P.)

Self-Responsibility

Heavily Suffered, Self-Responsibility

Suffered

3

TsunamiBreakwater for 50 Years R.P.

Self-Responsibility

Suffered, Self-Responsibility

Suffered

4

TsunamiBreakwater for 100 Years R.P.

Self-Responsibility (Almost Safe)

Secured

Secured

5

Moving of City to Safe Hillside

Self-Responsibility (Almost Safe)

Secured

Secured

6

Construction of Elevated Ground

Self-Responsibility (Almost Safe)

Secured

Secured

7

Elevated Tsunami Shelter

Self-Responsibility

Table 1: Response to the tsunami of 100 years return period

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CONCRETE TECHNOLOGY As the breakwater can disturb the fast flow of a tsunami and invasion at the initial stage, the refuge time of Case 3 can be prolonged compared to the case of no breakwater (Case 1) or the low breakwater (Case 2). Therefore, even the overflowing breakwater can be effective for indirect protection of human life. In addition, overflowing breakwater can disturb the flow of debris, to eliminate the sedimentation of the debris and mud after the tsunami, if the breakwater is resilient enough against overflowing.

The moving of the city to a safe hillside (Case 5) and the construction of the elevated ground (Case 6) are favoured solutions, if these are feasible.

The construction and maintenance of the tsunami facility should be considered since the definite and continuous action is crucial not only for the urgent crisis at present but also for the safety of future generations against the occurrence of mega-tsunamis.

Basic design of prestressed concrete tsunami breakwater The basic function of the tsunami breakwater is to protect the land by resisting severe earthquake forces before the invasion of the tsunami and by surviving, in case of the overflowing of tsunami water. Durable prestressed concrete structures are highly recommended for the breakwater due to the inherent resilient performance of the structures. Individually epoxy-coated strands for prestressing should be used to facilitate highly durable performance, say, more than 100 years durability. High durability is certainly inevitable for tsunami breakwaters.

Ground anchors with durable multiprotected prestressing cables should be adopted against buoyancy and instability of the breakwater, in case of overflowing.

Tsunami breakwaters must resist the pressure of return flow in case of overflowing.Therefore, the shape of the wall portion is symmetrical in the cross section as shown in Figure 1. The vertical

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prestressing cables must be placed at the central axis plane of the wall so that the prestressed force is quite effective in case of severe earthquakes.

In order to obtain feasible prestressed concrete structures, three typical breakwaters, having heights of 5 m, 10 m and 15 m, were investigated, as shown in Figure 1 and Table 2.

The design conditions are as follows: 1) The dynamic water pressure on the wall is assumed to be three times the static hydraulic pressure.

2) Prestressing cables have a 15.2 mm diameter and comprise seven wires coated with epoxy resin.

3) The full prestressing state is maintained under full height hydraulic pressure.

As the result of the calculation, the thicknesses of the bottom cross sections are 1.0 m, 1.8 m and 2.5 m for breakwater heights of 5 m, 10 m and 15 m, respectively. These values are shown in Table 2 together with the necessary amount of prestressing cables.

This feasibility study indicates that highly durable and resilient prestressed concrete tsunami breakwaters can be built quite economically.

The combination of fixed prestressed concrete breakwater with self-rising prestressed concrete breakwater would be one of the best harmonised counter-measures against mega-tsunamis.

Self-rising tsunami breakwater A self-rising tsunami breakwater wall, proposed by the author, is described specifically in [2], [3]. The basic concept of the structure is that of a concrete hollow box wall prestressed with external cables and laid down horizontally in the direction of the sea shore, which will rise automatically in an upright position by its buoyancy and seawater pressure in case of a tsunami invasion. As shown in Figure 2, the bottom end of the wall is connected to the footing by the prestressing external cables which are anchored at both the bottom of the footing and the tip of the wall. The height of the wall is representatively 10 m here, which will stand on the footing, having the elevation of 5 m above sea level.Therefore, total height of the wall will be 15 m from sea level.

Figure 1: Fixed prestressed concrete breakwater

h(m)

a(m)

b(m)

Prestressing Cables for 1 m Wall Length

5

0.8

1.0

One 12S 15.2,

10

1.0

1.8

Two and Half 19S 15.2

15

1.0

2.5

Six 19S 15.2

Table 2: Dimensions of breakwaters and amount of required prestressing cables

THE SINGAPORE ENGINEER October 2016

CONCRETE TECHNOLOGY

Figure 2: Self-rising tsunami breakwater

When a tsunami invades, the wall will rise up to the upright position, to resist a tsunami of less than 15 m height and the wall will return to the original position according to the return flow of the tsunami.The element of the wall is a precast prestressed concrete hollow panel having a depth of 1.5 m, width of 3 m and a length (height) of 10 m.The thickness of slab and web of the hollow concrete section is 15 cm.

The bending moment at the bottom of the wall at the upright position is 5000 kN-m for one element, so that six 19S15.2B (Japanese Industrial Standard) external cables are installed. The essential point of this structure is that the alignment or the length of the external cable continuing in the wall and the footing is not varied at the laid-down position and at the upright position, by arranging deviators at adequate locations. The suitable arrangement can be obtained by installing deviators at the length of 2.414 a from the end sections. Here, ‘a’ is the length of the cable location to the bottom surface of the wall element. The value of 2.414 can be obtained from cot (π/ 8) in geometry.

The rotation of the wall from laiddown to upright position can be performed at the curved shape of the footing portion at the contacting plane, similar to a hinge.

The nominal specific gravity of the element is less than 0.8 to get buoyancy. The maximum length of the break-

water would be 300 m, which consists of 100 wall elements connected to each other by dowel bars and low level prestressing. The water tightness of this breakwater is not significant because the length of time of the tsunami would be less than one hour.

Conclusions (1) The construction and maintenance of the tsunami facility should be considered such that the definite and continuous actions are crucial not only for the urgent crisis at present, but also for the safety of future generations against the occurrence of mega-tsunamis.

(2) The difficulty can be identified by the fact that the construction of a tsunami breakwater is intended to protect both human lives and the individual and social properties at the same time. To overcome this difficulty, a definite breakthrough is required.

The author has found a simple solution for the breakwater to protect the society and wealth of the nation.

The protection of lives must be treated separately.This simple concept can promote the construction of moderate-height breakwaters, where the height can be determined according to the wealth of the society and the desire of the people.

(3) As the breakwater can disturb the fast flow of the tsunami and invasion at the initial stage, refuge time can be prolonged compared to the case of no breakwater. Therefore, even the overflowing breakwater can be effective for the evacuation. In addition, the

overflowing breakwater can disturb the flow of debris, to eliminate the sedimentation of the debris and mud after the tsunami, if the breakwater is resilient enough against overflowing and return flow.

(4) Durable prestressed concrete structures are highly recommended for the breakwater, due to the inherently resilient performance of the structures. Individually epoxy-coated strands for prestressing should be used to facilitate a highly durable performance. High durability is certainly inevitable for tsunami breakwaters.

(5) The combination of fixed prestressed concrete breakwater with a self-rising one would be the best solution for a harmonised countermeasure against a mega-tsunami.

References [1] Ikeda Shoji, Machida A, Yamashita H: ‘Proposal of Stipulating a Rule for Prevention and Mitigation of Great Disasters’, Proceedings of the 5th International Conference on Protection of Structures against Hazards, November 2012, pp 63-68, Singapore.

[2] Ikeda Shoji: ‘Comprehensive Measures against Rare Mega-Tsunamis based on the Performance Creative Design Concept’, Proc Concrete Innovation Conference, Paper No 89, June 2014, Oslo, Norway.

[3] Ikeda Shoji: ‘Design of Seif-Lifting Tsunami Shelter and Self-Rising Tsunami Breakwater’, Proceedings of 39th Conference on OUR WORLD IN CONCRETE AND STRUCTURES, August 2014, pp 103-111, Singapore.

(This article is based on a Keynote Paper ‘Primary concept of the design of prestressed concrete breakwaters against mega-tsunamis’, authored by Shoji Ikeda, Professor Emeritus of Yokohama National University, Japan, and presented at the 40th Conference on ‘OUR WORLD IN CONCRETE & STRUCTURES’, which was held from 27-28 August 2015, in Singapore.

The conference was organised by CI-Premier Pte Ltd. More information may be obtained by contacting the author via email: ikeda@hybridresearch.co.jp).

October 2016 THE SINGAPORE ENGINEER

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PROJECT APPLICATION

The new Panama Canal Mapei was amongst the key contributors to this engineering feat.

The new Panama Canal project is considered to be the most ambitious project carried out in the world.

THE OFFICIAL OPENING The first ship to enter from the Atlantic side of the new Panama Canal was an enormous Chinese container ship (300 m long and almost 50 m wide, and carrying 10,000 containers on board), sailing under a Marshall Islands flag. The Cosco Shipping Panama, which had been renamed specially for the occasion, sounded its siren for more than two minutes, when it cut through the entrance ribbon at the new Agua Clara locks at 7:48 on 26 June 2016, after which it sailed across the artificial GatĂşn Lake and arrived in the afternoon, after an eight hour voyage, in front of the VIP stand erected next to the twin locks at Cocoli, on the Pacific side.

The President of Panama, Juan Carlos Varela, and a group of foreign Heads of State and Ministers were there to welcome this modern merchant vessel, a forerunner of those that will be arriving in the future.

Singing, dancing and spectacular fireworks were all part of the inau-

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On 26 June 2016, the Chinese container ship Cosco Shipping Panama entered from the Atlantic side of the new Panama Canal. It was welcomed by the President of Panama, Juan Carlos Varela, together with a group of foreign Heads of State and Ministers, and a crowd of people.

guration party for the 21st century canal, a project that has cost US$5.25 billion. It also represents a victory for this small state of just 4,000,000 inhabitants.

Seven years of work, 30,000 people working on site and a cost of over US$5 billion - these are just a few of the figures for the extension work

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done on the Panama Canal, that involved the construction of new locks on the Pacific side and on the Atlantic side, thereby allowing ships with three times the previous capacity to sail through. This is considered to be the most ambitious project ever carried out in the world, from an engineering point of view.

PROJECT APPLICATION BOOST TO MARITIME TRADE

A revolution in global maritime commerce is underway, as the new, 80 km long, inter-ocean canal has the capacity to double the yearly return for Panama to up to US$5 billion. A new type of ship with loads of up to 14,000 containers will be able to pass through the new canal locks which up until now could handle ships carrying only 4,400 containers. The Pacific and Atlantic ports, particularly in the US, have already carried out large-scale interventions, in order to handle these new ships, generating spin-off activities worth 20 times the cost of the work, equating to more than US$100 billion.

The first area to benefit from the expansion project has been the east coast of North America, because there is now a direct route from Asia, across the Pacific, instead of the longer route across the Mediterranean and Atlantic, which means two weeks less navigation time.

The ‘old’ canal, built by the Americans at the beginning of the last century, and which today still gives a return of US$2.5 billion, will continue to operate. Estimates foresee that income from the canal will double to US$5 billion dollars a year, once the new canal becomes fully operational.

The main client is still the United States who, on 31 December 1999, handed over administration of this precious waterway to Panama. But the Chinese are also active with their increasingly large merchant ships. The canal authorities are therefore already working on a future plan and are analysing the costs and benefits of a fourth route which may be even larger than the current one.

A HUGE PROJECT

The chambers of the new locks system are 427 m long, 55 m wide and 33 m deep.They act like giant lifts that raise the ships 27 m above the level of the ocean to the level of the artificial Lake Gatún and the navigable route that crosses the Isthmus of Panama,

to be then lowered down again on the opposite side, ready to set off on their oceanic voyage. Next to each chamber, the consortium has built enormous storage basins where the water is recycled - they allow more than 60% of this precious resource to be saved, and then fed back into the system of locks.

The construction of the new canal required the excavation of 70 million m3 of earth, as well as 290,000 tonnes of steel and 5.5 million m3 of concrete. More than 100 million hours of work went into the project.

The ‘jewel in the crown’ of the project is the 16 giant steel gates, built in Italy and transported via sea, over the course of seven years.

The average weight of each gate is 3,000 tonnes.The gates carry out their task in just five minutes - to open and close the water chambers which, operating like enormous lifts, allow the ships to overcome the 27 m difference between the levels of the two oceans and the artificial Lake Gatún.

SIGNIFICANT ITALIAN CONTRIBUTION

Interestingly, there is a significant Italian contribution to the project. The bulkheads and rolling gates, the technological heart of the entire project, were made in Italy by Cimolai. Also Italian-made is the operations software and many of the special construction materials which included bespoke products developed and supplied by Mapei, through consultancy work carried out by the company’s highly skilled technicians. The products include the latest generation of admixtures for concrete, waterproofing mortars, and special products for the structures and for waterproofing the storage basins.

Further, the Italian contractor, Salini-Impregilo, was part of the international Grupo Unido Panama Canal (GUPC) Consortium, the main contractor for the project. The consortium also included Sacyr, from Spain, Jan de Nul, from Belgium, and Constructora Urbana, from Panama.

KNOWHOW AND PRODUCTS FROM MAPEI Latest generation admixtures Through its subsidiary company, Mapei Construction Chemicals Panama S.A., Mapei supplied the latest generation of various admixtures, for the manufacture of around 5,500,000 m3 of mass concrete and marine concrete, used, respectively, to build the internal and external sides of the locks. DYNAMON XP2 and DYNAMON XP2 EVOLUTION 1 were developed specifically to build the new canal.

After numerous checks, carried out in the purpose-built Mapei laboratory in Panama, and cross-referencing the results with the GUPC laboratory, DYNAMON XP2 was chosen for use during the first six months of work on the project, on both the Atlantic side, where they were using Panama cement, and on the Pacific side, where they were using Cemex cement.

The objective was to guarantee a service life of 100 years for the work, with the use of a model that calculates the durability of concrete.

After commissioning the plants producing the concrete and aggregates, several serious problems, concerning the considerable reduction in mechanical strength and durability of the concrete produced by the plants, were solved.

In this phase, Mapei’s support focused on various activities - a study and chemical and mineralogical analysis of the raw materials used (basalt aggregates, pozzolan and cement); technical suggestions for the correct choice of flocculants and coagulants employed to treat the waters used to clean the aggregates so that they would be more chemically compatible with the superplasticisers used in the concrete mix; chemical and petrographic analysis; as well as control of the pozzolanic activity of the basaltic fines from the cleaning operations to assess its use in the concrete mix and optimise its natural pozzolan content.

Following a request from the client, Mapei started to develop a new product which could work well with

October 2016 THE SINGAPORE ENGINEER

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PROJECT APPLICATION the new mix designs being verified at the GUPC laboratory.

Mapei technicians formulated a new admixture called DYNAMON XP2 EVOLUTION 1, with the name chosen to give a sense of continuity to the enormous amount of work previously carried out on the old admixture. This product proved to be better at maintaining the workability and placement of the concrete at even lower dosage rates, compared with competitors’ products.

Renovating the existing canal The project also included restoration work on the original canal, put into service in 1912 and considered by many to be the most impressive concrete structure ever built.

Mapei was asked to offer a repair solution for the 30 m concrete columns that form an integral part of the structural concrete and steel framework of the ‘guillotine gates’ - massive gates raised and lowered by canal operators as they move ships, through the lock system, to and from both the Pacific and the Atlantic oceans.

These columns, referred to by Autoridad del Canal de Panamá (ACP), the client, as the ‘cut-waters’, stand in the centre of the 30 m diameter pipes and physically ‘cut’ the flow of water racing through the pipes into two distinct channels controlled by two parallel guillotine gates.

As a result of cavitation, chemical attachment, abrasion and impact from debris, the cut-water columns had been badly eroded, with large sections broken off and missing throughout. The structural integrity of the columns had been compromised to such a degree that the ACP engineers deemed it prudent to demolish them totally and re-cast them with a high-strength repair mortar.

Mapei’s technical representative assigned to this project recommended PLANITOP 15, a one-component, shrinkage-compensated cementitious mortar ideal for large-volume, low heat of hydration, form-and-pour and form-and-pump applications, and

32

MAPECURE SRA, a special curing admixture for cementitious mortars and concrete, to reduce hydraulic shrinkage and the formation of micro-cracks. Due to the scope of the repair involving hundreds of bags per column, PLANITOP 15 was extended 60% with washed pea gravel and modified with the maximum recom-

mended dosage of MAPECURE SRA. PLANITOP 15 was mixed and integrated with pea gravel by means of two large rotary-drum mobile mixers and then augured into the hopper of a concrete line pump which delivered the fluid mix to the operators 30 m below. The mortar mix was pumped, progressively filling forms until the

For this prestigious project, Mapei specially developed a new admixture for concrete, DYNAMON XP2 EVOLUTION 1, which proved to be excellent at maintaining the workability and application.

For the third set of locks, Mapei supplied synthetic waterproofing membranes, as part of the Water Saving Basins project.

THE SINGAPORE ENGINEER October 2016

PROJECT APPLICATION top of the 30 m pipe was reached.

The PLANITOP 15 and MAPECURE SRA worked flawlessly for the ACP repair crew which had only one week to complete the repairs and return the Gatun Locks to full service. The project engineers at ACP were extremely happy with the performance of the products and the on-site service and support provided by the Mapei technical representative.

Synthetic waterproofing membranes For the third set of locks, which completed the expansion work on the canal, an environmentally and socially sustainable project was drawn up, called the Water Saving Basins project, to limit its impact on the surrounding area, the people and the environment. In so doing, 60% less water will be required. Whereas normally, each passage requires around 500 million litres of water, the new system will need only 200 million litres.

Mapei contributed to this work with the synthetic membranes SIBELON PVC-P. The SIBELON trademark is owned by CarpiTech Sibelon.

Manufactured at the Polyglass (Mapei Group) plants, the membranes were used to waterproof the auxiliary basins that recover and partially recycle the water from Lake Gatún. Developed specifically for hydraulic works, SIBELON PVC-P synthetic membranes, laminated to non-woven polypropylene fabric, were installed over a total surface area of around 800,000 m2. Characterised by their high resistance to UV rays and aggressive atmospheric agents, they guarantee a high level of durability over the years.

Other products Mapei supplied numerous other products for completing this grandiose project, such as PLANIGROUT 300, MAPEGROUT 05/06, IDROSTOP PVC BI/BE, IDROSTOP MULTI 11, MAPEGEL UTT, IDROSILEX PRONTO, MAPEPROOF SWELL, IDROSTOP 10 and IDROSTOP MASTIC.

PROJECT DATA Project Panama Canal, Panama Period of Construction The new locks: 2010-2016 (the original canal was built during the period 1910 to 1916) Client Autoridad del Canal de Panamá (ACP) Design Mike Newberry, CICP, Panama Bernardo González, Grupo Unido

INTERVENTION BY MAPEI Period of the Intervention 2010-2016 Contribution by Mapei Supply of concrete admixtures, synthetic waterproofing membranes and other products

Panama Canal (GUPC), Panama (GUPC includes Sacyr Vallehermoso, Spain; SaliniImpregilo, Italy; Jan de Nul, Belgium; and Constuctora Urbana, Panama) Main Contractor GUPC Sub-contractors Cimolai, Italy Hyundai, South Korea Works Direction Bernardo Gonzales, GUPC

PROJECT HIGHLIGHTS IN FIGURES • 16 Gates - the new canal is based on a system of 16 gates (8 on the Pacific side and 8 on the Atlantic side). Each gate is 57.6 m long, 11 m wide and 30 m high, and weighs 3,000 tonnes. They allow ships to enter the waters of Lake Gatún.

Application for Mapei Products Renovating the existing Canal PLANITOP 15**, MAPECURE SRA Preparing the concrete used to build the new locks DYNAMON XP2, DYNAMON XP2 EVOLUTION 1 Waterproofing the basins SIBELON C 3250*, SIBELON C 3900*, SIBELON CNT 3750*, SIBELON CNT 4400* Other building works - PLANIGROUT 300, MAPEGROUT 05/06, IDROSTOP PVC BI/BE**, IDROSTOP MULTI 11**, MAPEGEL UTT, IDROSILEX PRONTO, MAPEPROOF SWELL, IDROSTOP 10, IDROSTOP MASTIC

• 800,000 m2 of synthetic membranes were installed for waterproofing the auxiliary basins used to recover and partially recycle water from Lake Gatún

[*The SIBELON trademark is owned by CarpiTech Sibelon.

The SIBELON membranes were manufactured at Polyglass (Mapei Group) plants]. [**These products are manufactured in the USA by Mapei Corp].

This editorial feature is based on an article from Realtà MAPEI INTERNATIONAL Issue 59. All images by Mapei.

• 30,000 people worked on site for the construction of the new Panama Canal • 5,500,000 m3 of concrete incorporating admixtures supplied by Mapei were used for building the inner and the outer sides of the locks

October 2016 THE SINGAPORE ENGINEER

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TRANSPORTATION ENGINEERING

Malaysia and Singapore sign MOU for the high speed rail project A Memorandum of Understanding (MOU) was signed on 19 July 2016 between the Government of Malaysia and the Government of the Republic of Singapore relating to the Kuala Lumpur-Singapore High Speed Rail (HSR) Project.

YB Datuk Abdul Rahman Dahlan, Malaysia’s Minister in the Prime Minister's Department and H E Minister Khaw Boon Wan, Singapore’s Coordinating Minister for Infrastructure and Minister for Transport, signed the MOU on behalf of their respective countries.

Held in Putrajaya, Malaysia, the signing ceremony, which was witnessed

by Malaysia’s Prime Minister Dato’ Sri Mohd Najib Tun Abdul Razak and Singapore’s Prime Minister Lee Hsien Loong, signifies Malaysia and Singapore’s firmest commitment yet to this iconic project.

The MOU reflects the outcome of extensive discussions between officials led by the Ministry of Transport and the Land Public Transport Commission (SPAD) of Malaysia, and the Ministry of Transport and Land Transport Authority of Singapore, since the project was first announced by the Prime Ministers of both countries at the 4th Singapore-Malaysia Annual Leaders’ Retreat in February 2013.

The MOU captures the key points of agreement on the project, which include the technical parameters; commercial model; customs, immigration & quarantine (CIQ) clearance; safety & security matters; regulatory framework as well as project management.

The MOU will guide the development of a legally-binding Bilateral Agreement to be signed by both Governments towards the end of this year. It also reiterates the Governments’ commitment to ensure that all project tenders are conducted in an open, fair and transparent manner, so as to encourage par ticipation from technology and

34

service providers worldwide.

Both Governments agreed that each will take responsibility for developing, constructing and maintaining the civil infrastructure and stations within their own countries, which will be undertaken by MyHSR Corporation and LTA (as InfraCos) in Malaysia and Singapore, respectively.

Through international tenders, an assets company (AssetsCo) will be appointed to provide and maintain the HSR trains and its associated systems (eg track, power, signalling and telecommunications), while two train operating companies (OpCos) will be appointed to operate the HSR services.

OpCo International will operate the cross-border services (ie the Express Service and the Shuttle Service), while OpCo Domestic will operate the Domestic Service within Malaysia.

Both Governments agreed that the HSR will have eight stations - the termini in Bandar Malaysia and Singapore, and six intermediate stations in Putrajaya, Seremban, Ayer Keroh, Muar, Batu Pahat and Iskandar Puteri.

All stations will be designed to integrate with the local public transport systems to ensure seamless connectivity. The trains will run at a top speed of more than 300 km/h. To facilitate swift and seamless travel, both Governments

Illustration of the 3 HSR services

Relationship and payment flows between InfraCos, AssetsCo and OpCos

THE SINGAPORE ENGINEER October 2016

TRANSPORTATION ENGINEERING agreed to co-locate CIQ facilities at three locations - Singapore, Iskandar Puteri and Kuala Lumpur - so that international-bound passengers will need to undergo CIQ clearance by both Malaysia and Singapore authorities only at the point of departure.

Both Governments also agreed to form a Bilateral Committee comprising representatives from both Governments to manage and regulate aspects of the project which might impact the cross-border services. In addition, a Joint Project Team comprising representatives from MyHSR Corporation and LTA will be formed to coordinate joint aspects of planning and development works prior to the commencement of operations.

As a next step, the Joint Project Team

Illustrative map of the location of the stations

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TRANSPORTATION ENGINEERING will call for an international tender to appoint a Joint Development Partner to provide technical support to both countries on the project.

Both Governments agreed to work towards commencing HSR operations by around 2026.

SPAD The Land Public Transport Commission or Suruhanjaya Pengangkutan Awam Darat (SPAD) is the planning, regulatory and enforcement authority for all

land public transport matters in Peninsular Malaysia. Established on 3 June 2010, under the Suruhanjaya Pengangkutan Awam Darat Act 2010, the commission falls directly under the purview of the Prime Minister of Malaysia.

MyHSR Corporation MyHSR Corporation Sdn Bhd (MyHSR Corporation) is a company incorporated in 2015, wholly owned by the Ministry of Finance Incorporated.

As the project delivery vehicle for

the KL-SG HSR project, MyHSR is responsible for the development and implementation of the project.

LTA The Land Transport Authority (LTA) is a statutory board under the Ministry of Transport of Singapore. The HSR Group within LTA will be responsible for the engineering design development and implementation of the project, working closely with relevant agencies in both Singapore and Malaysia.

Consortium wins contract to provide rail control for second line of Malaysia’s Klang Valley MRT A Bombardier TransportationGlobal Rail Sdn Bhd consortium has won the contract to provide the rail control and signalling system including platform screen doors (PSD) for the second line of Malaysia’s new Klang Valley Mass Rapid Transit (KVMRT) network.

The Bombardier-led consortium will deliver the proven BOMBARDIER CITYFLO 650 communications-based train control (CBTC) solution for the 52.2 km KVMRT Line 2, also known as the SSP Line, which will connect Sungai Buloh, Serdang and Putrajaya.

The six-year contract, awarded

by Mass Rapid Transit Corporation Sdn Bhd (MRT Corp), the owner and developer of the KVMRT project, has an overall value of approximately RM 433 million. Bombardier’s share totals approximately RM 220 million, with Global Rail’s share approximately RM 213 million.

Peter Cedervall, President Rail Control Solutions, Bombardier Transportation said, “Winning this second rail control contract for the KVMRT network reflects our customer’s confidence in our technology and delivery, and the

36

value we place on building longterm partnerships in our markets.

The new network will significantly improve transportation options for millions of people, and we look forward to continuing to work with Global Rail, MMC Gamuda JV and MRT Corp on both our projects which will have a major positive impact on the local environment and economy”.

Fan Boon Heng, Managing Director, Global Rail Sdn Bhd added, “We are very pleased to be working alongside Bombardier on this latest important project for Malaysia’s growth. Our partnership of globally-proven technology and experience matched with extensive local knowledge and expertise is ensuring the best transportation solution for the heavily-populated Greater Kuala Lumpur area. In addition, Bombardier and Global Rail have been committed partners in promoting the development of Malaysia’s rail industry and local expertise, which we will continue to jointly support throughout this latest project”.

Within the consortium, Bombadier will provide the design and engineering of the CITYFLO 650

THE SINGAPORE ENGINEER October 2016

CBTC solution for driverless operation for the line as well as onboard equipment for 58 vehicles.

Global Rail will be responsible for the PSD including automatic platform gates and the installation of the signalling solution. The contract will be delivered alongside project delivery partner MMC-Gamuda JV, responsible for the integrated delivery of the different civil works packages for the line.

Bombardier, together with Global Rail, is also delivering its CITYFLO 650 technology for the KVMRT Sungai Buloh - Kajang (SBK) Line 1 which will start full operation in July 2017. Both the SBK and SSP Lines are integral to the growth of the Greater Kuala Lumpur and Klang Valley Area, an important part of Malaysia’s Economic Transformation Programme. By 2022, the KVMRT network is expected to carry approximately 1,000,000 passengers per day. Other benefits will include reduced traffic, improved productivity, noise reduction and improved local air quality. Ultimately, the KVMRT network will be composed of three mass transit lines.

TRANSPORTATION ENGINEERING

The UK’s Crossrail project is more than 75% complete The Elizabeth line is a new railway for London and the South East, running from Reading and Heathrow in the west, through new tunnels under central London, to Shenfield and Abbey Wood in the east. The Elizabeth line is being delivered by Crossrail Limited.

The Elizabeth line will run from Reading and Heathrow in the west, to Shenfield and Abbey Wood in the east.

Overview The £14.8 billion Crossrail programme is currently Europe’s biggest infrastructure project. Construction began in 2009 at Canary Wharf, and the programme is now over 75% complete.

Half of the permanent track on the line has now been laid, and nearly all of the platform structures, which will give step-free access to the 200 m long trains at all of the 10 new stations, have also been built.

The project is proceeding on time and on budget.

Tunnelling finished in 2015 and Crossrail is now focussed on the complex job of fitting out the stations and tunnels with the equipment and systems needed to operate the railway.

This includes the installation of track, ventilation, power, signalling, communications and overhead line equipment, including over 15,000 km of cable.

There will be 40 Elizabeth line stations including ten new stations - at Paddington, Bond Street, Tottenham Court Road, Farringdon, Liverpool Street, Whitechapel, Canary Wharf,

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Sadiq Khan, Mayor of London (seated) makes first station-to-station journey from Custom House to Canary Wharf, along the Elizabeth line route.

Custom House, Woolwich and Abbey Wood.

Services through central London start in December 2018. The new railway will be fully integrated with Transport for London’s (TfL) existing transport network.

New state-of-art trains will carry an estimated 200 million passengers a year. The new service will reduce journey times, increase central Lon-

THE SINGAPORE ENGINEER October 2016

don’s rail capacity by 10% and bring an extra 1.5 million people to within 45 minutes of central London.

Fitting out the railway A fleet of bespoke machines is used in the fit-out of the tunnels. Four giant multi-purpose gantries, which have been specifically designed for Crossrail, carry and locate the track in the tunnels, before it is concreted into place. Special floating track slab

TRANSPORTATION ENGINEERING is used in sections of the tunnels to minimise noise and vibration where concert halls and recording studios are located directly above.

The contractor undertaking the Crossrail railway systems main works, contract C610, is ATC, a Joint Venture comprising Alstom, Transports Sud Ouest (TSO) and Costain Limited.

Crossrail’s electric trains will be powered by overhead lines on the surface sections of the route and by an overhead catenary system in the new tunnels. Over 4 km of full height platform edge screens will be fitted at stations. These will help with the circulation of air and will maintain temperature levels along with huge vent fans that will be installed at 18 locations across the route. The edge screens will also incorporate passenger information displays and space for advertising.

Railheads The two main temporary logistics centres for Crossrail’s railway systems are located at Plumstead in southeast London and Westbourne Park in west London. These will be used by the many different engineering trains during the fit-out of the tunnels and stations.

Plumstead is the larger of the two railheads with a total of eight tracks, an overhead gantry crane to supply engineering trains and an operations centre to coordinate the activity.

At Westbourne Park, the previous railhead that was constructed for the transport of excavated material from the western tunnels is replaced with a new three track railhead. The materials needed for the western tunnels fit-out will be stored and loaded onto construction trains at a temporary storage depot at Old Oak Common and brought to the Westbourne Park railhead.

Track installation Crossrail is using five different types of track in its tunnels: • Standard track slab - this forms 80% of track on Crossrail’s central section • Direct fixed track - used in the Victorian engineered Connaught Tunnel • High attenuation sleepers - similar to

standard slab, it is used only in a few small areas to reduce noise/vibration • Floating track slab light - used to reduce noise and vibration underneath Soho • Floating track slab heavy - used to reduce noise and vibration underneath the Barbican The majority of the track in the central section is formed from standard track slab. This connects with the other track forms that are used at specific locations. A total of 41.2 km of standard track slab will be installed on Crossrail, using fibre reinforced concrete.

Direct fixed track has been used within Connaught Tunnel. The track bed is a concrete reinforced structure. It allows engineers to create a flat surface on top of the significant undulations in the ground and to work within the height restrictions which are a feature of this Victorian engineered tunnel.

Floating track slab (light) is used between Tottenham Court Road and Bond Street to minimise noise and vibration impacts from the operating railway on nearby recording studios and hotels, which is a requirement of the Crossrail Act. The track slab floats on a combination of Elastomet rubber bearings and heavy duty springs.

The track slab is constructed and then jacked up to accommodate the bearings and springs. A total of 1.97 km of floating track slab (light) will be installed on Crossrail.

Floating track slab (heavy) is used

in the Farringdon area due to the close proximity of the Barbican. It sits on heavy duty springs. A total of 1.34 km of floating track slab (heavy) will be installed on Crossrail.

Due to the extra depth added by the spring base of the floating track, a shallower sleeper is needed.

To ensure that the shallower sleeper remains durable and effectively minimises noise and vibration, dense concrete called Magnadense is used.

Magnadense is over twice as dense as normal concrete, due to its natural iron ore content.

Multi-purpose gantry When constructing the standard track slab, the initial sequence of work is carried out by four multi-purpose gantries which transport and accurately position around 70,000 sleepers and 57 km of rail in Crossrail’s central section. Each gantry, operated by a single person, runs along the raised curbed sides of the tunnel’s first stage concrete.

After positioning 108 m long sections of rail along a stretch of tunnel, the gantry then carries and deposits sleepers at carefully measured intervals, before lifting the rail into place on top of them. The track is then secured in place using clips, props and jigs before it is welded and the formation is concreted into position.

Two gantries operate from Plumstead, one from Westbourne Park and the other installs the floating

Permanent Elizabeth line track installed through Woolwich Station

October 2016 THE SINGAPORE ENGINEER

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TRANSPORTATION ENGINEERING track slab underneath the Barbican estate.

A specialised welding machine is used to join the 108 m long sections of Crossrail’s permanent rail together.

Concreting train The 465 m long concreting train is a sophisticated mobile underground concrete batching factory and plays a key role in creating the standard track slab.

Dry materials are loaded onto the concreting train which then batches the concrete.

It is based at Plumstead and is used in the installation of standard track slab. At its peak production rate, it is able to install up to 250 m of concrete track slab a day.

When the concreting train is not operating in the tunnels, it is split in two, due to its size, and is located on two of the eight railhead tracks.

Running and maintaining the concreting train is a 24-hour operation.

Concrete pouring takes place during the night with restocking and maintenance being carried out during the day.

Concreting shuttle A concreting shuttle is used to construct the standard track slab in the tunnels between Royal Oak Portal in west London and central London.

Pre-mixed fibre reinforced concrete, provided by a batching plant at Paddington New Yard, is loaded onto the shuttle.

Drilling rig As part of tunnel fit-out, over 250,000 holes will be drilled to accommodate brackets for cabling, walkways and other equipment to support the operation of the railway.

ATC Joint Venture will deploy a state-of-the-art, precision automated drilling rig which will drill many of the holes required, minimising the need for manual drilling.

Once the track slab has been laid, the rig will sit on the track and move its way through the tunnels, drilling the holes in pre-determined locations.

The machine has a dust suppression system in place, producing a clean and accurate drilled hole every time. The drilling rig works in conjunction with real-time 3D laser surveys of the tunnel, to ensure accuracy.

Powering Crossrail The Crossrail route will be powered by a 25 KV overhead line system. A catenary system will be installed in the tunnels, which includes a rigid overhead conductor bar which makes contact with the train’s pantograph to draw overhead power.

In the central section, traction power for the Crossrail trains will be provided by two new bulk supply points from National Grid - at Pudding Mill Lane in the east and Kensal Green to the west.

A 22 KV high voltage network will be installed in the central section, from Royal Oak Portal in the west to

Multi-purpose gantry used to place rail and sleepers in tunnels

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THE SINGAPORE ENGINEER October 2016

Limmo Peninsula in the east, with an 11 KV high voltage non-traction spur to be installed from Limmo through to Plumstead. This network will supply mains power to each Crossrail station, shaft and portal within the central section.

Signalling Crossrail will initially operate up to 24 trains per hour in each direction through central London, during peak periods. The new signalling system will incorporate Automatic Train Operation to support the delivery of a high-frequency metro service and will also be capable of enhancement, for the operation of over 30 trains per hour through the central section, at a later date.

Due to the integration of Crossrail’s central section with the existing National Rail network, Crossrail services will need to operate with existing signalling and safety systems installed at either end of the Crossrail tunnels.

Crossrail opted for a Communications Based Train Control (CBTC) signalling system for the central section, as it is technically and operationally proven and successfully used by many metro systems around the world.

Crossrail’s communications and control systems New communications and control systems will be installed throughout the new Crossrail stations and tunnels. These include: • Customer Information systems Customer Information displays in ticket halls and concourses and at each platform screen door.

• CCTV - Digital cameras for station control and security. Camera views of the platform are transmitted to the driver's cab for driver only operation (DOO).

• Radio – Provision of radio infrastructure / network for operations and emergency services.

• Public Address System – For general and emergency announcements.

All images by Crossrail Limited

TRANSPORTATION ENGINEERING

Bentley Systems contributes to Crossrail success Building Information Modelling (BIM) is at the core of how the Crossrail project is being built on time and on budget.

The project has been designed in a virtual environment for 3D, 4D, and 5D BIM, powered by Bentley Systems’ comprehensive modelling software which captures data - physical, environmental and commercial - on every element designed for the project.

“Over 13,000 people have had to enter, create, and review data in the Crossrail project. They are from all disciplines and include electrical engineers, structural engineers, tunnelling experts, rail track experts, mechanical systems designers and others, and all these people had to interact with a digital model”, said Jeremy Shaffer, Senior Director, Transportation Operations & Asset Management, Bentley Systems Inc, USA. “Oftentimes, just on one station, you could have 10 to 15 companies with different expertise having to review the model and resolve clashes”, he added.

Bentley Systems is software supplier and technology par tner to Crossrail and its supply chain. It is also involved in the progression of BIM processes and standards including BS1192, PAS1192 and COBie to aid the design, construction and operation of the new Elizabeth Line.

Crossrail uses MicroStation, Bentley Systems’ flagship product for the architecture, engineering, construction, and operation of all infrastructure types, as well as ProjectWise, Bentley Systems’ engineering information management platform. Including the workflows and standards within BS1192, ProjectWise provides Crossrail with a single ‘source of truth’ for design information across

the entire project team, wherever they are and whenever they need it.

While a main reason for choosing Bentley Systems was its federated approach to information management / modelling via ProjectWise, another key factor was the availability of a number of applications on Bentley Systems’ common V8i data platform.

To manage and mitigate Crosrail’s exposure to risk on the project further, it mandates the use of over 40 different Bentley Systems’ design and analysis applications, across multiple disciplines, on the project.

At the core of Crossrail’s Asset Information Management System (AIMS) is Bentley Systems’ eB software which controls asset information throughout the lifecycle of change. Crossrail use AIMS to capture the published version of the design and put it under change control, for transmittal of all document types to contractors and stakeholders, contract administration, transmittal of early warning notices from contractors, capturing as-built records, and organising information for hand back.

Bentley Systems’ asset information management solution, AssetWise, based on the company’s eB technology, manages the engineering and asset information in the Crossrail project and provides a complete, federated view of ‘digital railway’ information.

Bentley Systems recently announced that it has successfully upgraded Crossrail’s Common Data Environment (CDE) for asset information through Bentley’s AssetWise managed services to a hybrid cloud-computing platform powered

by Microsoft Azure. This provides a single location for storing, sharing, and managing information for approximately 1,000,000 assets.

Jeremy Shaffer

Mike Coldrick

Crossrail Bentley Information Academy The Crossrail Bentley Information Academy is an undertaking of the technology partnership between Bentley Systems and Crossrail Limited. It provides hands-on training to the Crossrail supply chain on the latest technology and software being used to design and build the new railway including BIM. The academy helps to ensure Crossrail is capturing, developing and sharing BIM best practices with the entire Crossrail supply chain, focussing on people, process and technology.

“What Crossrail wanted to do was to explain to their supply chain how important they understood Crossrail’s best practices and their processes, what the deliverables should be and in what data format the deliverables should be”, said Mike Coldrick, Vice President - Transport & Local Infrastructure EMEA, Bentley Systems (UK) Ltd. “So Crossrail explained everything to the supply chain, up front, as to what information they needed and what processes, workflows and good practices are needed, to make sure the project is a success. The communication with and involvement of the supply chain proved crucial to the success of Crossrail”, he added.

Crossrail and Bentley collaborated on all aspects of setting up the academy, with Crossrail providing project expertise and Bentley facilitating the physical learning environment.

October 2016 THE SINGAPORE ENGINEER

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EDUCATION

UON Singapore celebrates 10th Year Anniversary with Awards and Gala Dinner UON Singapore, a wholly owned entity of the University of Newcastle, Australia, has completed 10 years of delivering educational excellence to the region, with over 4,000 students from 37 countries having successfully completed the various courses offered.

To commemorate this milestone event, an Awards and Gala Dinner was held on 22 July 2016, at Mandarin Orchard, with more than 200 guests attending, including students, alumni, partners, sponsors and friends. The night of celebration brought together students from various programmes.

The students also had the opportunity to meet distinguished individuals including His Excellency Mr Phillip Green OAM, Australian Trade Commissioner to Singapore, the Guest-of-Honour at the Awards and Gala Dinner; Prof Caroline McMillen, Vice Chancellor and President of the University of Newcastle, Australia as well as members of the Australian Alumni Singapore, UON Singapore Alumni Chapter, and UON Singapore’s Board of Directors.

The celebrations included the presentation of 36 awards in recognition of the outstanding achievements of current students and staff, including an Engineers Australia Sponsor Award for demonstrating sustainability in final year projects. The winner of this award was applauded for his project titled ‘Improved Biomass Cookstove for Developing Countries’.

The project was further extended to an innovative version of a smart and sustainable biomass and solarpowered cook stove (ECOTRACK), which secured the third rank, under Category 4 (Universities), in the Energy Innovation Challenge (EIC). EIC was organised as part of the National Engineers Day (NED) 2016 and hosted by the Institute of Engineers Singapore (IES). Four electrical and mechanical students within the project

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His Excellency Mr Phillip Green OAM, Australian Trade Commissioner to Singapore, the Guest-of-Honour at the Awards and Gala Dinner and Prof Caroline McMillen,Vice Chancellor and President of the University of Newcastle, Australia, spoke on the occasion.

team from UON Singapore, received a trophy and a cheque of S$3,000 from Ms Indranee Rajah, Senior Minister of State for Law and Finance, at the NED 2016 Closing Ceremony, held at the HDB Hub Atrium on 24 July 2016. EIC was jointly organised

by Science Centre Singapore and IES, and supported by the Ministry of Education as well as the National Research Foundation.

Programmes in Engineering and Built Environment This year, UON Singapore will also witness the graduation of the first cohort of students pursuing the Bachelor of Construction Management (Building) (Honours) programme, at a ceremony to be held this November. UON Singapore has partnered with BCA Academy to run the programme, in both part-time and full-time modes, since 2013. The UON Bachelor of Engineering (Honours) (Civil) programme will also be launched in February 2017 with BCA Academy.

Future direction UON Singapore will continue to expand the delivery of programmes in the areas of business, commerce, communication, construction management, engineering, environmental and occupational health and safety, as well as information technology, through strong partnerships with leading local institutions.

With internationally qualified research-intensive academics and a teaching and learning adviser based in Singapore, UON Singapore is committed to connecting students to new ideas and novel ways of thinking, and equipping them with a world-class education that will open doors across the region and the globe.

With a growing student body, UON Singapore represents an international footprint of the University of Newcastle, Australia.

More information can be obtained from newcastle.edu.au/singapore.

Dr Yeap Peik Foong, UON Singapore Academic Director, with award winners at the Awards & Gala Dinner on 22 July 2016.

THE SINGAPORE ENGINEER October 2016

IES UPDATE

Seminar on Singapore Standard for Specification for Steel for the Reinforcement of Concrete – Weldable, Reinforcing Steel – Bar, Coil, and Decoiled Product (SS 560 : 2016) The revision of the Singapore Standard for Specification for Steel for the Reinforcement of Concrete – Weldable, Reinforcing Steel – Bar, Coil, and Decoiled Product (SS 560 : 2016) was approved by the Building and Construction Standards Committee on 25 May 2016, to include the use of high grade reinforcing steel bars and couplers (Grade 600).

To inform the industry of this latest change, a seminar was organised by the Standards Development Organisation @ The Institution of Engineers, Singapore (SDO@IES), supported by BCA, on 15 July 2016.

Attended by more than 300 participants from about 180 organisa-

tions, the seminar provided an update on the newly revised SS 560 : 2016 and highlighted the use of the higher strength Grade 600 steel reinforcing bars (rebars), new bar rib geometry and other key changes over the old SS 560 : 2010 standard.

Additionally, test methods and factory production control certification in accordance with SS 560 : 2016 were shared at the seminar. Rounding out the topics of the day was a discussion on the current design restrictions based on Eurocode 2 and how Grade 600 rebars and couplers could be used effectively to improve productivity in cage construction and column design. TSE

A seminar participant directing his questions to the speakers during the panel discussion, moderated

by Mr Chan Kok Way, Chairman, Building and Construction Standards Committee.

Seminar on Singapore Standards for Air Conditioning, Mechanical Ventilation and Indoor Air Quality (SS 553 : 2016 & SS 554 : 2016) More than 400 participants from 200 organisations attended the Seminar on Singapore Standards for Air Conditioning, Mechanical Ventilation and Indoor Air Quality on 11 August 2016. The Seminar was organised by the Standards Development Organisation at The Institution of Engineers, Singapore (SDO@IES) and supported by the National Environment Agency (NEA), the Building and Construction Authority, the Association of Consulting Engineers and the Singapore Green Building Council.

The Seminar provided an update on the newly revised SS 553 (Code of practice for air-conditioning and mechanical ventilation in buildings) and SS 554 (Code of practice for

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indoor air quality for air-conditioned buildings) which affect energy consumption and indoor environment quality in most buildings.

These two standards, adopted by the Building and Construction Authority as part of the Green Mark assessment criteria, will help to reduce energy consumption in the building sector.

Mr Khoo Seow Poh, Deputy Chief Executive Officer of the National Environment Agency, delivered the Welcome Address. Participants learnt about the key changes in the revised standards, the correlation between these two standards, as well as how these two standards were being used as part of the Green Mark assessment criteria. This was followed by a robust

THE SINGAPORE ENGINEER October 2016

Q & A session, led by Mr Chan Kok Way, Chairman of the Building and Construction Standards Committee.

In conjunction with the seminar, there was also a mini exhibition which showcased the products and services related to these standards. TSE

Mr Steven Kang (right), Business Development Director at Measurement & Verification Pte Ltd, speaks with Dr Ng Lee Ching (fifth from right), Director of NEA’s Environmental Public Health Division, as Mr Chan and Mr Khoo (third and fourth from right respectively) look on.

IES UPDATE

Through our very own eyes: The WiSER Leadership Biodiversity Trail

by Er. Emily Tan Er. Tan gives a first-hand account of her experiences on a short, fruitful journey to Singapore’s second-oldest reservoir.

The IES Women in Science, Engineering & Research (WiSER) Committee organised a Leadership Biodiversity Trail at Lower Peirce Reservoir on 31 August 2016.

About 20 of us, both committee and regular IES members, joined Ms Isabella Loh, Chairman of Singapore Environmental Council (SEC) and Mr Zac Lim, SEC Manager for Biodiversity to learn more about the natural world and its connection with human beings, particularly engineers and leaders.

Lower Peirce Reservoir is Singapore’s second-oldest reservoir. The forest that lines its banks is considered mature secondary rainforest with many visible reminders of the past when vast areas of Singapore were covered with plantations.

Entering the Lower Peirce Trail from the well-hidden entrance just off Casuarina Road, it felt like we were entering a secret forest; an entirely different world altogether. In the blink of an eye, we were whisked away from the hustle and bustle of the city and into a world of fresh air, surrounded by special flora and fauna and even forest animals which Isabella and Zac were quick in spotting and pointing them out to us.

Indeed, Nature is a great inspiration for engineering! Isabella shared with us that the invention of the bullet train was inspired by the kingfisher.

The Japanese engineers modelled the shape of the bullet train after the kingfisher which has a long, hard and narrow beak and yet is very silent as it moves.

She also mentioned that in the early days, fishermen used the trunk

Participants of the Leadership Biodiversity Trail with Ms Isabella Loh, Chairman of Singapore Environment Council (7th from right)

of the Nibong palm to make stilts in kelongs (traditional offshore fishing platforms and dwellings) as it was slender and rot-resistant. The tree also provided natural needles to sew the fishing nets.

Drawing similarities between human relationships and Nature, Isabelle proceeded to highlight an example of mutually-beneficial symbiosis in our surroundings: The Mahang plant.

Also known as the Ant plant, it is the ‘safe haven condominium’ for ants.

The ants are able to obtain shelter in the stem of the plant, while the plant

benefits as the ants act as a natural defence against herbivorous insects.

Just as in the natural world; we need to maintain good relationships with our counterparts and help each other in order to live in harmony.

As we carried on trekking through the trail, some of us spotted flora and fauna such as fig, durian and Tembusu trees, the Sunda scops owl and various species of bats. Isabella and Zac were very enthusiastic to share with us their knowledge on biodiversity, in the process improving our awareness about environmental sustainability.

Er. Emily Tan, Chairman,WiSER Committee (grey & orange shirt) and other participants listening intently to the safety briefing by Mr Zac Lim, Manager (Biodiversity), SEC, before the start of the trail.

October 2016 THE SINGAPORE ENGINEER

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IES UPDATE

Ms Yeo Ying Sze,WiSER Committee Member & lead organiser of this event leading the way to the reservoir.

The trail led us all the way to the reservoir. With lush, green forests on our left and the clear, blue waters of the reservoir on our right, the picturesque scene provided us with a brief respite from the stressful, high-tempo nature of our daily working lives.

As a bonus, we were treated to a breath-taking view of the peaceful reservoir under the setting sun shortly after we reached.

At the end of the trail, we all gathered round for an inspiring dialogue session with Isabella, during which she shared snippets of her life experiences, her values and enlightened us on the reasons she gave up her corporate life to serve on the Singapore Environmental Council.

“Everyone has their own values; it's best to follow with your own heart, maintain those values and live happily as yourself,” she said.

That evening, not only did we gain inspiration from the nature around us, we too learned many valuable lessons from the leadership experience that Isabella shared with us. The Leadership Biodiversity Trail was definitely an insightful one! TSE The author is the Chairman of the IES WiSER Committee, which seeks to address the various issues related to the representation of women in the fields of science, engineering and research.

Imperative for REs and RTOs to continue nue improving their knowledge: ACES Nine Exemplary Site Supervisor Awards also given out at annual al event to recognise re nise se efforts of REs and RTOs

Er. Chua delivering the Welcome Address.

Due to the highly built-up nature of Singapore, construction projects will become increasingly complex as Singapore moves towards the third decade of the 21st century.

To continue keeping up with the challenges of site supervisory work, Resident Engineers (RE) and Resident Technical Officers (RTO) need to constantly refresh what they know, so as to remain relevant and future-ready.

These remarks were made by Er. Chua Tong Seng, Vice President of

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the Association of Consulting Engineers Singapore (ACES), at the RE/ RTO Awards Night 2016, held on 23 September 2016 at the Matrix Auditorium @ Biopolis.

“Projects are (becoming) more complex and closer to neighbouring properties, buildings are rising higher up to the sky and underground structures are going deeper into the ground. It is important that REs and RTOs stay relevant with knowledge and local regulations, and continue to upgrade yourselves to be in tune with the future demand,” he said.

The guest-of-honour for the event was Er. Chew Keat Chuan, Commissioner of Building Control and Group Director of the Building Engineering Group at BCA. The annual RE/RTO Awards Night is a platform for REs and RTOs in the civil and structural engineering industry to meet fellow colleagues and

THE SINGAPORE ENGINEER October 2016

catch up with old friends. It is hosted on a rotating basis between IES and ACES. More importantly, it is the occasion where the Exemplary Site Supervisor Award (ESSA) is given out. Conferred jointly by IES and ACES and supported by BCA, the ESSA recognises outstanding REs and RTOs for their exceptional dedication as site supervisors of structural works, and their contributions to construction safety and productivity.

Guests taking fun shots at the photo booth that was set up for the Awards Night.

IES UPDATE

The ESSA recipients pose for a group photo after receiving their award certificates and cheques from Er. Chew (sixth from left, wearing tie).

All eyes and ears on Er. Chong as he talks about projected future demand for infrastructure projects.

Mr Tong (left) keeping the audience engaged with a little bit of stretching before his talk.

A total of nine REs and RTOs received the ESSA this year. Mr Justin Su, an RTO with some 30 years of experience, is one of them.

“I am extremely happy and proud to receive this award as it represents my contribution to the construction industry after so many years. Now I have something to talk about after I retire!” said the 63-year-old with a chuckle.

Mr Su makes it a point to reach his worksite at 7.30am each morning and

pays close attention to every single detail, from housekeeping and safety regulations to formwork and so on, helping to ensure that the site is managed properly. According to him, “not even an unattended box of nails” will escape his eagle eyes.

Echoing Er. Chua’s advice to REs and RTOs on lifelong learning, Mr Su says that he keeps himself abreast of safety regulations and technical developments by attending courses, talks and so on.

In addition, he imparts his experience to REs and RTOs many years his junior and advises them on softer skillsets such as leadership and communication, in the process reinforcing his own learning through teaching.

A series of talks on various aspects of construction practices in Singapore was also held that evening.

Starting the ball rolling was IES Immediate Past President Er. Chong Kee Sen, who discussed the future of Singapore’s infrastructure projects from a multidisciplinary perspective.

Next on stage was Er. Pham Thanh Hai from BCA, who highlighted the key challenges of underground construction site supervision and showcased what the future of this field could potentially be like.

Mr Desmond Lim of the Corrupt Practices Investigation Bureau was on hand to enlighten guests on how to safeguard against corruption, sharing a few case examples from within the construc tion industry to illustrate his pointers.

The final speaker for the evening was MOM’s Mr Tong Tee Hui, who spoke about the recently-gazetted Design for Safety regulations and how REs and RTOs could contribute to the DfS process throughout a construction project’s life cycle.

The evening’s proceedings concluded with a lucky draw, adding a dash of festive cheer to the RE/RTO Awards Night. TSE Full List of Exemplary Site Supervisor Award 2016 Winners Perumal Moorthy Guo Jin Rong Aung Khine Zaw Tan Bee Loke Su Haw Kuong Justin Low Tiang Thong Muhammad Faizal Bin Abdullah Kanagarajan Arivarasu Tan James Malenab

October 2016 THE SINGAPORE ENGINEER

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IES UPDATE

An honest-to-goodness conversation on career development

Mr David So (standing) speaks to Rolls-Royce Singapore employees about IES and the Chartered Engineer programme.

Rolls-Royce Singapore employees listening intently as IES Secretariat staff explain the process of applying to become a Chartered Engineer.

Mr David So sharing some of his experiences with two participants.

The lifeblood of many an organisation is its people – the resource that gets other resources mobilised. This maxim has not been lost on Rolls-Royce Singapore (RRS), which hosted a ‘career conversation’ for some 150 employees on 30 September 2016.

Held at its Seletar campus, the event showcased various career development options and specialisations within the company, should employees wish to diversify their skillsets and experience a change in environment.

Several professional institutions were also invited to this event. Apart from IES, local branches of the Institute of Electrical and Electronics Engineers, The Institute of Engineering and Technology, The Institute of Marine Engineering, Science and Technology and the Institution of Mechanical Engineers were represented.

IES Council Member and Vice Dean of the College of Fellows, Mr David So, was on hand to introduce the Institution and offer some insight into the potential opportunities offered through the Chartered Engineer programme.

According to RRS, $65 million was invested in helping its employees learn and develop professionally last year.

Demonstrating its commitment towards employee growth and progress, it was announced during the event that the company would sponsor 80% of the membership fees for professional bodies.

Seemingly piqued by this announcement, a regular stream of participants were observed around the IES booth over the course of the half-day event. Many of the queries were related to the process of becoming a Chartered Engineer, which were answered by the secretariat staff present.

IES is grateful to have had the opportunity to reach out to RRS employees. The company’s forward-looking, people-centric company culture certainly stands out as a model that can be emulated by others. TSE ADVERTISERS’ INDEX IMI HYDRONIC ENGINEERING ––––––––––––– PAGE 37 INDUSTRIAL CONCRETE ––––––––––––––––– PAGE 11 PRODUCTS SDN BHD MAPEI FAR EAST PTE LTD –––––––––––––––––– PAGE 25 MITSUBISHI ELECTRIC –––––––– OUTSIDE BACK COVER MULTININE CORPORATION PTE LTD ––––––– PAGE 43 STRAINSTALL SINGAPORE PTE LTD –––––––– PAGE 35 SUPER GALVANISING –––––––––––––––––––––––––– PAGE 3

The “Career Conversation”, split into two sessions, attracted roughly 150 employees across all arms of Rolls-Royce Singapore.

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THE SINGAPORE ENGINEER October 2016

WORLD ENGINEERS ––––––––––– INSIDE FRONT COVER SUMMIT 2017