A study on seismic retrofit of multi-fab plants in Taiwan's hi-tech industry

Abstract

This study investigates the seismic hazard potential of multiple-fab plants increasingly adopted by Taiwan's hi-tech industry. A typical double-fab plant for wafer foundry in Hsinchu Science-Based Industrial Park (HSBIP) is considered for case study. Dynamic analysis of the objective double-fab plant using the ground excitation recorded near the HSBIP during the 1999 Chi-Chi earthquake has been carried out. Analysis indicates that large story drifts and damages are concentrated in the soft stories where the clean-rooms are located. Seismic retrofit of the wafer foundry plant with soft-and-weak stories using a displacement-dependent metallic yielding damper is proposed to increase the stiffness and damping of the structure. Analysis shows that the peak reductions of the story drift can reach as high as 70 percent if properly designed. The proposed retrofit strategy using metallic yielding dampers proves to be effective and sufficient.