Seismic Rehabilitation of Santa Monica Place Mall Based on ASCE 41

摘要

This paper presents the seismic design and remodeling of Santa Monica Place mall and its seismic strengthening following the guidelines of ASCE 41-06. The original building was designed as a closed roof mall based on the 1976 Uniform Building Code. The remodeled mall is designed to be an open roof mall with about same plan dimensions as existing mall. The existing mall is a steel frame with inverted Chevron (V-type) concentric braced frames in the N-S direction and CMU shear walls in the E-W direction. A nonlinear two-dimensional push-over analysis is conducted on representative braced frames to demonstrate nonlinear post-buckling capacity of Chevron braced frames. It is found that plastic rotation of the beam, where two braces intersect, at target displacement is less than the limits defined by ASCE 41-06. It was found that the existing braced frames have a lateral load carrying capacity greater than the demands according to the 1976 UBC and ASCE 41-06. To improve the seismic performance of the inverted braced frames, the beam in each frame that is intersected with the braces was strengthened. The strengthening scheme ensures that the expected post-buckling lateral load capacity exceeds the lateral shear demands.