IFRC SRU SD Michal Sladek Retrofitting before and after

RETROFITTING before and after disaster

by Michal Slรกdek

Content: - overview on retrofitting techniques - retrofitting in humanitarian shelter - challenges of retrofitting

- Definition: Definition „Retrofitting refers to the addition of new technology or features to older systems.”

- In this context: “Retrofitting is the intervention on shelter that decreases vulnerability towards natural threats.“

Retrofitting in humanitarian context

Random rubble masonry wall

Strengthening walls

Brick masonry wall

Rainforced concrete wall

Additional reinforced concrete layer - „jacketing“

Masonry column jacketing

Strengthening elements

RC column jacketing Reinforced concrete beam jacketing

Seismic belt tightening

tightening of projection with a steel rod

detail of belt on lintel level seismic belt around the building

installing of seismic belt

Strengthening integrity

strengthening the openings

Timber construction

truss to top plate strapping

strenghtening

purlin to rafter strapping

additional cross-bracing

stud to top plate strapping

anchor bolts for wall-tofoundation connection

Timber construction strengthening

adaptable steel elements

prefabricated steel elements

wire

nails

screw s

bolts

ground screw mesh rebar

straps hooks

welded web

plates and angles

– Steel is principal constructional material in retrofitting practise.

Most of the techniques are introducing steel elements into the existing parts of vulnerable buildings.

Steel in retrofitting

During „standard“situation, just vertical loads are exerting

During hurricane or earthquake, also lateral loads arise

For the vertical loads, parts of To deal with accidental loads, the structure can be just laid on structure has to behave as a on the other block

*What makes vulnerable buildings: - Lack of knowledge ?

- Lacke of resources ?

Vulnerability of non-engineered structures

BUILDING POLICIES

EMERGENCY SHELTER

RETROFITTING TRANSITIONAL SHELTER

PERMANENT HOUSING

Disaster management cycle and shelter

Retrofitting practise after emergency: - Local technical knowledge - Simple technologies - Local materials - Driven by families

Retrofitting in emergency

Good use of tarpaulins from IFRC shelter kit in Myanmar 2008 The image cannot be display ed. Your computer may not hav e enough memory to open the image, or the image may hav e been corrupted. Restart y our computer, and then open the file again. If the red x still appears, y ou may hav e to delete the image and then insert it again.

During reconstruction after the floods, imporved design of traditional hut was introduced. Uganda 2007. The design of hut was „retrofitted“. „retrofitted“

Plinth foundations on plastic sheet Roof elements wire strengthening

Reconstruction phase – build back better

Core 200 shelter Sri Lanka 2008. The resistant structure can be finished by owners.

Initial deing

Initial design with good resistance: steel reinforcment in structural elements and corrugated iron roof.

Development phase – core approach

before retrofitting

after:

seismic belt crossbracing wall-toroof connectors

Sultan Dagi high school, Kasmir Mitigation by retrofitting

* 8 October 2005 an earthquake hits Kasmir.

(Sultan Dagi school suffered just moderate damage).

-> Documentation and assessment of damage has been made -> -> Decision about retrofitting was taken -> -> Engineered project was prepared -> -> Retrofitting has been realised. realised

Drawings and execution

Note: This is a multi-room public edifice, designed and engineered.

Retrofitting process

Rising awarness is a part of mitigation activities: Retrofitting instruction should take place, as at this informational poster from Bangladesh for owner-driven retrofitting.

HOWEVER, emerging issues like: - population growth - urbanisation in disaster prone areas - non-engineer use of modern material are making retrofitting complex

Mitigation

Evaluation table of retrofitting for humanitarian use advantages

obstacles

- sustainable solution – helps to build resilient communities

- expensive solution, requires an invasive intervention on building

- displacement of housing or people is avoided

- high level of engineering is required*

- self-driven and stepwise retrofitting possible

- time consuming procedure (assessment, project, realisation)

- less resources are used compared to building new NOTES: *More heavy the structure is, more complex is the retrofitting.

Cost of retrofitting is relevant in consideration the possible collapse.

Evaluation

Resistant building = resources + time + knowledge - In post-disaster period, there is lack in resources and affected community is often in pressing situation.

- Resistance can be added in several steps over a longer period of time, when resources become available.

- Knowledge is the part, where most of improvements can be made in every stage of humanitarian response. Not only concerning local communities and authorities, but as well donors and humanitarian actors.

Design should consider the possible retrofitting in future.

Resistance and retrofitting conclusion

Retrofitting is part of the humanitarian response tools. Though it has a specific position and principal challenges to face: - How to spread quite sophisticated technical knowledge into the communities and also to local authorities?

- After humanitarian shelter intervention, how to keep the level of construction once the humanitarian mission is over?

- How to rise resources for retrofitting. In post-disaster period most resources are in use for the affected families, which became homeless. In pre-disaster period the is no emergency. Can international humanitarian organisation act in some areas because af high risk?

Can there be a humanitarian response without disaster?

Oustanding challenges

Acknowledgements for principal source of illustrations: UNESCO/UNDP India „Manual for Restoration and Retrofitting of Rural Structures in Kashmir“ Prepared for UNESCO by Rajendra Desai, Rupal Desai and the team of the National Centre for Peoples’- Action in Disaster Preparedness (NCPDP). India, 2007 UN Habitat „IASC Emergency Shelter Cluster SHELTER PROJECTS 2008“ UN Habitat 2008 UN Habitat „IASC Emergency Shelter SHELTER PROJECTS 2009“ UN Habitat 2009 Zarins, Jake „‘CORE 200’ SHELTER INTERVENTION PROJECT REPORT & METHODOLOGY DISCUSSION“ Norwegian refugee council, Sri Lanka 2008 & Myanmar Red Cross Society 2008.

RETROFITTING before and after disaster Michal Sládek michalsladek@stonline.sk

Thank you for your attention!