2024 EERI Annual Meeting (2024AM)

Building Codes and Building Performance

Among important structural performance objectives, collapse prevention is most closely tied to loss of life and catastrophic property damage.  This session seeks to provide a thumbnail answer to the title question, with reference to recently completed FEMA projects.

Consideration of Collapse in ASCE/SEI 7-22

This is an overview presentation on the current state of design practice with respect to collapse, as standardized in ASCE/SEI 7-22.

Improving Performance of Buildings in Very High-Seismic Regions

This project investigated the increased risk of collapse of new buildings in regions of very high seismicity and developed recommendations for improving seismic codes to mitigate this risk.

Numerical studies using nonlinear models of different seismic-force-resisting systems provide computed probabilities of collapse for archetypes of varying height, strength, and displacement capacity over a broad range of maximum considered earthquake ground motion levels.  The analytical results show greater-than-desired probabilities of collapse.  The FEMA P-2343 report provides recommendations for conceptual changes to ASCE/SEI 7 to address deficiencies.

Seismic Evaluation and Retrofit of Multi-Unit Wood-Frame Buildings with Weak First Stories

Older, multi-unit wood-frame buildings with brittle, weak, and torsionally irregular stories have collapsed in past earthquakes. Often designated as soft, weak, or open-front (SWOF) buildings, many were constructed in the 1950s through 1970s and can be found across the United States.

The FEMA P-807-1 report aims to advance the understanding of the behavior of SWOF buildings and encourage improved practice in the design of retrofits to address collapse potential.

Recommendations for Cordoning Earthquake-Damaged Buildings

Following a damaging earthquake event, it is common practice to place fencing, barricades, or cordons around damaged structures to provide safety against potential collapse or falling debris.

The FEMA P-2055-2 report presents recommendations for determining the cordon area for individual damaged buildings (considering collapse and debris shadow areas) and identifies considerations for managing the cordon area.