Relative Seismic Risk Evaluation of Various Buildings Based on an Input Wave Field

Abstract

Seismic responses of various buildings are calculated by a three-dimensional (3D) linear method for examining the soil-building interaction based on an input seismic wave field in the reclaimed zone of Tokyo Bay in which ground motions include a considerable amount of surface waves. A seismic wave field means seismic waves propagate in a 3D medium. The method was recently proposed to adequately treat surface waves trapped by a deep (several kilometers) underground structure in a soil-building interaction system. First, seismic responses of a building were calculated at two soft-soil sites for three large earthquakes to understand the variations in building responses with reference to sites and earthquakes. Second, seismic responses of low- to high-rise reinforced concrete (RC) and steel buildings and wood buildings were compared at a soft-soil site for a large earthquake, evaluating the relative seismic risk of various buildings. Midrise RC and steel buildings shook more severely than low-rise and high-rise RC and steel buildings. Flexible wood buildings suffered extremely large interstory drifts, indicating the largest seismic risk.