Locally Produced Structural Elements for Fast Rebuilding

1. Locally Produced Structural Elements for Fast Rebuilding Dr. Gary S. Prinz Steel Structures Laboratory (ICOM) EcolePolytechniqueFederale de Lausanne (EPFL)

2. Introduction Natural Disasters/ Conflicts: - Displace large numbers of people - Require massive-rebuilding effort, in short timeframe. INDONESIA (2004) 9.1Mw earthquake/tsunami displaces 500,000 people 2 HAITI (2010) 7.0Mw earthquake displaces 1.2M people 1 Current Conflicts Example Natural Disasters [1] Margesson, R., and Taft-Morales, M. (2010). “Haiti earthquake: crisis and response” Congressional Research Service, Library of Congress, Washington, D.C. [2] Meisl, C.S., Safaie, S., Elwood, K.J., Gupta, R., and Kowsari, R. (2006). “Housing reconstruction in Northern Sumatra after the December 2004 Great Sumatra Earthquake and Tsunami.” Earthquake Spectra, 22(S3), S777-S802.

3. Introduction Typical Shelter Construction: 1) Steel frames with light cladding - Specialized steel elements - Multiple fasteners and skilled labor often required - Elements must be stored in preparation for use/or manufactured post disaster. 2) Timber frames with heavy-light cladding - Timber elements require an abundance of natural resources Time Consuming Space Consuming Skilled/trained construction (to withstand future events) Ecological impacts (deforestation) Can degrade over time (water, insects, etc.)

4. Introduction Typical Shelter Construction (Cont.): 3) Adobe/Cementitious Material Shelters - Requires large quantities of materials (difficult to transport) - Difficult to dismantle and move to permanent location - Heavy, and vulnerable to aftershocks/future earthquake events if unreinforced. Shelter Needs: - Cheap, locally fabricated structural elements - Mountable and dismountable by small group of unskilled labor Following 2004 Indonesia quake, residents chose temporary tents over ‘transitional shelters’ due to fear of not relocating back to villages.2 - Resistant to future disaster events - Ecologically efficient [2] Meisl, C.S., Safaie, S., Elwood, K.J., Gupta, R., and Kowsari, R. (2006). “Housing reconstruction in Northern Sumatra after the December 2004 Great Sumatra Earthquake and Tsunami.” Earthquake Spectra, 22(S3), S777-S802.

5. Multi-Purpose Elements Idea: Use existing materials/elements who’s use can be modified during extreme circumstances to create shelter structures. - Existing fabrication technology on large scale (modified purpose) - Fast response - No storage (minimal storage) of specialized structural elements - Can be re-used for original purpose when/if no longer needed as shelter! Shelter Fabrication Storage Exportation (Small connectors) (Local production) Storage Exportation Assembly Assembly

6. Multi-Purpose Elements 1) Steel-Coil Tubes: - Easily manufactured from thin galvanized steel coils - Used as ventilation ducts in industrial buildings, with existing fabrication technology available almost anywhere in world! - Good structural properties (high flexural stiffness, etc.) - Durable 2) Rain Gutters: 3) Door Frames: - Have structural properties 4) Guard Rails: - Mass production already exists in many parts of the world - Can be used for primary purpose if no longer needed

7. Inter-Connecting Tubular Structures Example Multi-purpose element use: - Use tube elements to form structural frames - Easily store end connectors Rigid end-connecting elements Special end-connecting elements - Divert production of tubes following disaster

8. Inter-Connecting Tubular Structures Steel Log-Cabin (SLC) Concept: (0.10 m3 steel) 0.46 m 0.46 m 0.46 m - Steel tubes form primary structure and function as façade - Interlocking joints allow speed and ease in assembly - Easily dismounted and relocated - No need for fasteners/skilled labor - Formed entirely from thin galvanized steel coils

9. Tube Connectors Crimped Connector -Attached using crimping machine -Fabricated from steel plates (same as tubes) -Can stored flat, and folded on site to facilitate large quantities.

10. Experimental Testing of SLC Concept Shelter Must Withstand Future Natural Events: - Aftershocks from devastating earthquakes - Recurring hurricanes/ wind storms

11. Testing of SLC System System-Level Lateral Resistance Tests: No intermediate shear connectors Crimped end connectors Intermediate shear connectors

12. Testing of SLC Concept Tested to 2kN S E N W East Wall: - Various West Wall: - Tube shear connectors - Door opening

13. Testing of SLC Concept S E N W North and South Wall: - Tube shear connectors - 1 cycle to 2kN - Pushover to failure

14. Testing of SLC Concept North Wall

15. Development of Tube Connectors Crimped Connector Proposed Semi-Rigid Connector -Less Material -More material -Low rotational stiffness -Possibly higher rotational stiffness -Requires crimping machine on-site -Restrained in tube by friction (no special machines required) - No mechanical fasteners!

16. Testing of Tube Connectors Crimped Connector Static, monotonic loading to failure Semi-Rigid Connector

17. Testing of Tube Connectors Crimped Connector

30. Testing of Tube Connectors Semi-Rigid Connector 3x increase in strength 4x increase in stiffness

31. Summary - High demand for shelters exists following major natural disasters - Quick response time is required to preserve both life and livelihood - Need for easily assembled locally fabricated shelters - Typical 3 stage rebuilding process (emergency shelter, transitional shelter, permanent shelter) takes too long. - Use of multi-purpose elements offer fast rebuilding solution - Possible to use existing elements for modified purpose (i.e. ventilation ducts) to create light, adaptable, durable, and locally fabricated shelter solutions. - Multiple configurations available (example SLC concept, frames, etc.) - Reduces required storage - Special connectors required - Pushover testing of SLC shelter indicates connecting elements are crucial to shelter performance, and must be developed thoroughly for good performance.

32. Questions? / Discussion References: [1] Margesson, R., and Taft-Morales, M. (2010). “Haiti earthquake: crisis and response” Congressional Research Service, Library of Congress, Washington, D.C. [2] Meisl, C.S., Safaie, S., Elwood, K.J., Gupta, R., and Kowsari, R. (2006). “Housing reconstruction in Northern Sumatra after the December 2004 Great Sumatra Earthquake and Tsunami.” Earthquake Spectra, 22(S3), S777-S802.