Seismic evaluation and retrofit of a moment frame building with viscous dampers

Abstract

This study investigates the seismic performance level of an existing multistory steel building based on FEMA 356 criteria. The building consists of several pre-Northridge moment resisting frames and gravity frames. The structure’s seismic performance level was determined based on story drift criteria. Linear Dynamic Procedure (LDP) with seven Maximum Credible Earthquake (MCE) time history records suitable for this site was used. The results demonstrate that this building is seismically deficient. The building is successfully retrofitted with diagonally positioned fluid viscous dampers on several moment frames. The study included numerical simulation with SAP 2000 where acceptable dampers were selected based on their force and stroke to match commercially available dampers.