Adjacency Issues in Soft-Story Wood-Frame Buildings

April 29, 2011
Publication: Structural Engineers Association of Northern California
Author(s): David McCormick Bruce F. Maison David Bonowitz Laurence M. Kornfield

Reports results of computer simulation study on the seismic pounding of four-story, wood-frame corner buildings that are common in the city of San Francisco. The study calibrated two building computer models to simulate actual earthquake response and assessed collapse performance under twenty-two hypothetical pounding situations of both as-built soft-story and retrofitted buildings. For this building type a typical pounding situation increased the collapse rate by 14 percent at design earthquake intensities. For retrofitted versions of the building in a typical pounding situation, pounding slightly decreased the collapse rate. However, there were factors that appear to significantly increase the collapse rate especially in combination: negligible building separations, and multiple adjacent buildings having low effective damping and large mass. Based on these results an approximate way to account for pounding within the context of current design procedures is outlined.

Services: Structural Design