SEISMIC PERFORMANCE ANALYSIS OF WENCHUAN HOSPITAL STRUCTURE WITH VISCOUS DAMPERS

摘要

Analytical investigation was undertaken to assess the seismic performance of Wenchuan Hospital located in Wenchuan county, southwest China's Sichuan province, where a severe earthquake has occurred in May 2008. The structure consists of a four-storey reinforced concrete frame with viscous dampers. The irregular building is 18-35-m tall and has a total floor area of 17 000 m~2. Viscous dampers are set along the outside surface of structure to get a more efficient reduction of structure responses. The design idea of performance-based seismic design is presented in this paper. Seismic performance of the structure with and without viscous dampers under different levels of ground motion is analysed and verified by different methods, including elastic analysis under frequent earthquake, unyielding and elastic check of structure element under medium earthquake, static nonlinear analysis and dynamic nonlinear analysis under rare earthquake. And a comparative analysis is presented, such as results between elastic and inelastic analysis, static nonlinear analysis and dynamic nonlinear analysis, and structure with and without viscous dampers. The control effects of viscous dampers on internal force, deformation and energy dissipation of the structure are also studied. Meanwhile, a practical method to calculate the supplemental damping ratio added by viscous dampers is proposed for elastic analysis with dampers. After a series of analysis, the performance objective of the structure can be well verified.