RETROFITTING

before and after disasterby Michal Sládek

Content: Content: Content: Content: - overview on retrofitting techniques

- retrofitting in humanitarian shelter

- challenges of retrofitting

- DefinitionDefinitionDefinitionDefinition: „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

decreases vulnerability towards natural threats.“

Random rubble masonry wall Brick masonry wall Rainforced concrete wall

Strengthening walls

Additional reinforced concrete layer - „jacketing“

Strengthening elements

Masonry column jacketing 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

Strengthening integrity

installing of seismic belt

strengthening

the openings

Timber construction

strenghtening

purlin to rafter

strapping

truss to top

plate strapping

additional

strapping

stud to top

Timber construction strengthening

additional

cross-bracing

anchor bolts

for wall-to-

foundation

connection

stud to top

plate strapping

adaptable adaptable adaptable adaptable steel elements

nails screw

s bolts

ground screw

wire

prefabricatedprefabricatedprefabricatedprefabricated steel elements

ground screw

straps

hooks

mesh

rebar

Steel in retrofitting

plates and angleswelded web

–––– Steel is principal constructional material in retrofitting practise.Steel is principal constructional material in retrofitting practise.Steel is principal constructional material in retrofitting practise.Steel is principal constructional material in retrofitting practise.Most of the techniques are introducing steel elements into the existing parts of

vulnerable buildings.

During „standard“situation, just

vertical loads are exerting

During hurricane or earthquake,

also lateral loads arise

For the vertical loads, parts of

the structure can be just laid on

on the other

To deal with accidental loads,

structure has to behave as a

block

Vulnerability of non-engineered structures

*What makes

vulnerable buildings:

- Lack of knowledge ?

- Lacke of resources ?

BUILDING POLICIES

EMERGENCY SHELTER

TRANSITIONAL SHELTER

RETROFITTING

Disaster management cycle and shelter

PERMANENT HOUSING

Retrofitting practise

after emergency:

- Local technical knowledge

- Simple technologies

Good use of tarpaulins from IFRC

shelter kit in Myanmar 2008 The image cannot be displayed. Your computer may not have enough memory to open the image, or the image may have been corrupted. Restart your computer, and then open the file again. If the red x still appears, you may have to delete the image and then insert it again.

- Simple technologies

- Local materials

- Driven by families

Retrofitting in emergency

During reconstruction after the floods, imporved

design of traditional hut was introduced. Uganda

2007. The design of hut was „retrofitted“„retrofitted“„retrofitted“„retrofitted“.

Plinth

foundations

on plastic

sheet

Roof elements

wire

strengthening

Reconstruction phase – build back better

strengthening

Initial deing

Core 200 shelter Sri Lanka 2008. The resistant

structure can be finished by owners.

Development phase – core approach

Initial design with good resistance: steel reinforcment in

structural elements and corrugated iron roof.

before

retro-

fitting

after:

seismic

belt

cross-

Mitigation by retrofitting

Sultan Dagi high school, Kasmir

cross-

bracing

wall-to-

roof con-

nectors

* 8 October 2005 an earthquakeearthquakeearthquakeearthquake hits Kasmir.

(Sultan Dagi school suffered just moderate damage).

-> Documentation and assessmentassessmentassessmentassessment of damage has been made ->

-> Decision Decision Decision Decision about retrofitting was taken ->

-> Engineered projectEngineered projectEngineered projectEngineered project was prepared ->

-> Retrofitting has been realisedrealisedrealisedrealised.-> Retrofitting has been realisedrealisedrealisedrealised.

Drawings and execution

Retrofitting process

Note: This is a multi-room public

edifice, designed and engineered.

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: 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

advantagesadvantagesadvantagesadvantages obstaclesobstaclesobstaclesobstacles

- 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*

avoided

- 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

Cost of retrofitting is relevant in consideration the possible collapse.

Resistant building = resources + time + Resistant building = resources + time + Resistant building = resources + time + Resistant building = resources + time + knowledgeknowledgeknowledgeknowledge

---- In post-disaster period, there is lack in resources and affected ---- 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.

Resistance and retrofitting conclusion

communities and authorities, but as well donors and humanitarian actors.

Design should consider the possible retrofitting in future.

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 - 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

Can there be a humanitarian response without disaster?

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 theNational Centre for Peoples’- Action in Disaster Preparedness (NCPDP). India, 2007

UN Habitat„IASC Emergency Shelter Cluster SHELTER PROJECTS 2008“UN Habitat 2008UN 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

RETROFITTING before and after disaster

Michal Sládek

michalsladek@stonline.sk

Thank you for your attention!

& Myanmar Red Cross Society 2008.