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FEMA’s Mitigation Assessment Team Program – Where Have We Been and Where Have We Still To Go? 2010 ASFPM National Conference John Ingargiola – FEMA Eric Letvin – URS. Presentation Outline . Program Overview – Where Have We Been? What Has Been the Effect of the MATs?
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FEMA’s Mitigation Assessment Team Program – Where Have We Been and Where Have We Still To Go?2010 ASFPM National Conference John Ingargiola – FEMAEric Letvin – URS
Presentation Outline • Program Overview – Where Have We Been? • What Has Been the Effect of the MATs? • Common Vulnerabilities / Recommendations • Areas of Future Research / In-Depth Studies
Objectives of the MAT Program • Conducts forensic engineering analyses to determine causes of structural failure and success • Provides recommendation that communities, states and organizations/agencies can take to reduce future damages and protect lives and property in hazard areas • Increase damage resistance through improvements in construction codes and standards, designs, methods, and materials used for both new construction and post-disaster repair and recovery
Where Have We Been? • Nine events since Hugo (Andrew, Iniki, Opal, Fran, Georges (Gulf Coast and Puerto Rico), Charley, Ivan, Katrina, and Ike • Size of the deployments and reports have grown – we have also branched out to manyorganizations, agencies,and universities.
Benefits of the MAT Studies • MAT observations and recommendations have served as valuable contributions to several other guidance documents, including (FEMA 55, 543, 550) • Codes and Standards • Florida Building Code (Glazing, Asphalt Shingles, Tile Roofing) • ASCE 7 Wind Standard • Coastal A Hazard, ASCE-24 (Updated ASCE 24-05 Flood Design Standard, ASCE 24-05 adopted by ICC) • Windborne Debris – Florida legislature removed panhandle exemption • Louisiana enacted statewide building code, Mississippi coastal counties enforce IBC/IRC, Florida Building Commission work group developing comprehensive flood provisions for the Florida Building and Residential Codes
Site Specific Damage Factors Besides storm characteristics, damage appears to be a function of the following; • Age of construction and building code used • Quality of construction and building code compliance • Architectural features (e.g., gable versus hip roof) • Quality and age of the flood maps—this determines building elevation and extent of flood zones • Local site conditions, such as soils types, erosion rates, severity of waves, topographic effects (wind), amount and size of flood and windborne debris, and local drainage effects • Building component degradation due to corrosion or termites
Site-Specific Damage Factors Local site requirements, such as: • Building setbacks • Land use • Height restrictions House at Poipu Beach after Iniki with transported lava rock. Lava rocks were a local site condition that served as debris, causing additional damage to many structures.
Common Vulnerabilities / Recommendations • 75% / 25% rule for flooding • Every MAT has surprising / significant recommendations • Many common vulnerabilities / recommendations from NC to TX and HI
The embedment depths specified for pile foundations should be sufficient to ensure the foundation will withstand anticipated erosion and storm forces. Foundation
When waves reach above the floor system of most elevated buildings, those buildings will be heavily damaged or destroyed. Exceeding the minimum lowest floor elevation requirements of the NFIP can reduce residual flood risk. BFE = 16 ft NGVD, Floor at 21.5 ft Floor at +/- BFE Building Elevation & Freeboard
When a slab-on-grade is constructed below an elevated building in a coastal area subject to wave action, it should be designed and constructed in such a way that it will not damage the building foundation when acted on by flood forces. Concrete Slabs Below Buildings
Siting of buildings close to eroding shorelines puts those buildings at risk and often results in loss of those buildings to erosion and flood effects. Siting Daulphin Island, AL after Hurricane Georges
Buildings should be designed and constructed to at least the minimum requirements in the IBC/IRC or State and local codes if those codes are more stringent. Buildings constructed to modern building codes demonstrate significantly improved building performance. Building Codes Adjuntas, PR after Hurricane Georges
The MATs have consistently found numerous significant performance problems that are directly related to construction workmanship deficiencies. There is a need for increased inspections by designers or third-party inspectors. Inspection Inadequate sheathing attachment – Hurricane Katrina
Although there are many worthy areas of research in the field of building science and natural hazards, the MAT has noted a few specific areas where researchers can provide a greater understanding to architects, engineers, building code officials, as well as local officials and home/business owners. Areas of Future Research / In-Depth Studies
Understanding the local effects of erosion and scour will greatly enhance the siting and design of future structures in coastal areas. Scour Foundation scour was reported to be 10 feet deep at this house on the Bolivar Peninsula, TX, after Hurricane Ike.
Debris from adjacent house Damaged Pilings Floodborne Debris A better understanding of floodborne debris and its effects would help design better foundation systems in the future
Other Areas of Potential Research • Coastal Flood Velocities • Windborne Debris • Climate Change • Water Infiltration
Area of Unacceptable Performance: Critical Facilities All MATs have noted that, in general, buildings functioning as critical and essential facilities have not performed better than commercial buildings.
As future hurricanes will undoubtedly impact the MS to TX coast, there will be an opportunity to study the effect of these events on the built environment and the success of the buildings built in the aftermath of the 2005 – 2008 hurricanes. The Future?