泸定地震中藏式博物馆RC框架结构震害成因分析OA

During the September 5,2022 Luding earthquake,a Zang-style concrete frame museum on a special site was seriously damaged.Investigations revealed that the failure causes included:topographic amplification effect of ground motion,beam-column joint with Queti detail exacerbating the"strong beam-weak column"effect,and incorrect reinforcement detailing of frame columns leading to insufficient ductility.To analyze the seismic damage causes,an integrated platform topography-structure model was established,incorporating the special joint details.Additionally,a solid finite element model of beam-column joints with the Zang-style Queti detail was developed to investigate the influence of joint configurations and reinforcement details on the seismic performance of the overall structure and individual components.Compared with simplified topography amplification factor approaches,the topography-structure interaction model yields damage locations and severity more consistent with the field survey,indicating that current codes underestimate amplification factors for such topographic conditions.Modified Zang-style joint reinforcement details can effectively reduce damage at the end of first-story frame columns.For frame structures on special sites with distinctive joint details,the following recommendations are proposed:conduct site-specific seismic response analysis to determine appropriate topography amplification factors;establish integrated topography-structure interaction models for seismic verification;characteristic decorative components should be separated from the main structure,stiffness of the unseparated joint to the overall structure and component should be considered,and the column stirrup densified region should be measured from the lower edge of the haunched beam.