基于性能的大跨径斜拉桥 H 形桥塔纵向地震易损性分析

Analysis on Longitudinal Seismic Vulnerability of H-type Pylon of Long-span Cable-stayed Bridge Based on Performances

摘要:

我国许多地区都处于板壳活跃地带，近年来，由于板壳活动的加剧遭受了多次不同程度的地震灾害，给人民带来了较大的生命财产损失。在地震作用下，作为斜拉桥主要受力构件的主塔若发生损伤，将使斜拉桥整体损伤风险明显提高。因此，以某斜拉桥为工程实例，通过SAP2000有限元分析软件，基于性能抗震设计理论学科知识，利用IDA时程分析结果，根据能力需求比模型法绘制出斜拉桥主塔各关键截面的地震易损性曲线，然后对斜拉桥主塔进行地震易损性分析。结果表明：纵桥向地震作用下，主塔的中塔底截面为易损截面。

Abstract:

All the regions in China are in the active zone of plate and shell. In recent years, due to the intensification of plate and shell activities, the regions have suffered many different degrees of earthquake disasters, which has brought great loss of life and property to the people. Under the action of earthquake, if the main pylon as the main load-bearing component of cable-stayed bridge is damaged, the overall damage risk of cable-stayed bridge will be significantly increased. Taking a cable-stayed bridge as an engineering example, through SAP2000 finite element analysis software, based on the performance seismic design theory subject knowledge, by using the IDA time-procedure analysis result and according to the capacity demand ratio model method, the seismic vulnerability curve of each key section of the main pylon of the cable-stayed bridge is drawn, and then the seismic vulnerability analysis on the main pylon of cable-stayed bridge is carried out. The results show that under the action of longitudinal earthquake, the bottom section of the middle pylon of the main pylon is a vulnerable section.