Performance Based Seismic Retrofit of the Los Angeles Downtown Women's Center Project

Abstract

This paper describes the performance based seismic rehabilitation of a historic 1920’s vintage 6-story non-ductile concrete shear wall building which is being remodeled to be reused as an abused/homeless women’s shelter. The building is located in the blighted “skid-row” district of downtown Los Angeles and is part of the City’s adaptive reuse and redevelopment program. The retrofit objective was to obtain a Life Safety performance level under BSE-1. The work followed the relevant requirements of ASCE41-06, LABC 2008 and the LADBS Adaptive Reuse Ordinance (ARO). The analysis consisted of a Linear Dynamic Procedure (LDP) used as a baseline followed by a Nonlinear Static Procedure (NSP) to capture nonlinear behavior. The retrofit scheme was implemented by adding a couple of new cast-in-place concrete shear walls and shotcreted shear walls at certain existing wall locations. Other measures included foundation augmentation, gravity column fiber-wrapping along with some roof mass reduction.