不规则钢筋混凝土梁桥抗震性能评价的N2方法.pdfVIP

_______________________________________________________________________________ , (, , , 116024) Pushover N2 FajfarN 2 SDOF MDOF N2 P315.9 A N2 Method for Seismic Performance Evaluation of Irregular RC Bridges WANG Dong-sheng, WANG Guo-xin, AI Qing-hua State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology, Dalian 116024, China Abstract: A combined non-linear method by pushover analysis and time history analysis is presented to evaluate the seismic performance of irregular RC bridges. This method is named as N2 method that was firstly developed by Fajfar in structural seismic damage analysis, where N stands for non-linear, and 2 for two separated models. Pushover analysis of the every typical pier of the bridge is carried out by using single pier model. Displacements at top of the pier for different damage limited states and “capacity curve” of the pier are obtained. Damage limited states, which are represented by displacements at top of the pier by transforming from moment-curvature relationship of the section in plastic hinge zone, are defined by both of the strain of concrete or longitudinal steels in plastic hinge zone and shear strength of the section. Then demanded seismic displacements on the pier are calculated by non-linear time history analysis using the integral bridge model. The seismic performance of the bridge is evaluated by means of comparing the capacity of the pier with the seismic demands. A continuous curved bridge is taken as example to illustrate the application of the method finally.