Evolution of Predicted Seismic Performance for Wood-Frame Buildings: Fid-Bau Portal

Evolution of Predicted Seismic Performance for Wood-Frame Buildings

Sutley, Elaina J. / van de Lindt, John W.

Following natural disasters, major changes are often adopted in design codes, provisions, and guidelines that highlight existing or perceived deficiencies in design code calibration and sometimes design philosophy. The work presented herein chronicles the evolution of seismic design for wood-frame buildings from 1959 through current state-of-the-art methodologies available as of 2015. Included in the approaches in this study were two performance-based seismic retrofit levels and a soft-story-only retrofit design that followed a recent guideline published by FEMA. A brief background on the historical significance and major changes adopted in each provision or guideline is provided. Building performance was quantified and compared using multirecord fragilities for a range of wood-frame building types for the historical seismic provisions, demonstrating that the predicted seismic performance of wood-frame buildings has improved over time. It was also demonstrated that performance-based seismic retrofits can be designed to multiple levels of seismic performance, including a superior level, which provides immediate occupancy of all building types following maximum considered earthquake (MCE) ground motions. The superior-level retrofit reduced the predicted peak interstory drift of a 3-story soft-story building by 90%. The information gained in this study can be incorporated into community loss estimation models and used to expand the knowledge base on how seismic risk has changed over time with respect to the wood-frame building inventory.