超大跨斜拉桥顺桥向地震损伤分析与控制-《建筑科学与工程学报》

文章信息/Info

Title:: Seismic Damage Analysis and Control of Super Long-span Cable-stayed Bridges in Longitudinal Direction

Author(s):: XIE Wen, SUN Li-min; School of Architectural, Civil Engineering and Environment, Ningbo University

Keywords:: super long-span cable-stayed bridge; extreme earthquake; failure criterion; failure pattern; damage control strategy

摘要:: 以一座试设计的主跨1 400 m的斜拉桥为例，采用弹塑性方法并引入地震损伤指标分析了不同强度地震作用下飘浮体系和弹性约束体系的地震损伤与破坏模式；研究了极端地震作用下损伤控制策略对斜拉桥损伤控制效果的影响。结果表明：极端地震作用下，主塔和桥墩分别遭受局部失效和严重损伤，发生了典型的弯曲单塑性破坏；基于Park损伤指数的附加耗能阻尼器的损伤控制策略可显著控制主塔、桥墩地震损伤和主梁位移，满足损伤控制目标要求，改善了桥梁的整体抗震性能。

Abstract:: Elastoplastic analysis method was carried out to investigate the seismic damage and failure modes of a trial designed cablestayed bridge with a main span of 1 400 m including floating system and elastic restrained system under various ground motion intensities. The influences of damage control strategies on damage control effect of cablestayed bridges were presented. The results show that the pylons and piers suffer from local failure and severe damage under extreme earthquake respectively, which are subjected to a typical failure mode with one plastic hinge. The damage control strategies with additional dampers have obvious effects on controlling seismic damage of the pylons and piers, which can effectively reduce the girder displacement in the longitudinal direction. Therefore, it is effective to improve the seismic performance of a trial designed cablestayed bridge so that its seismic performance can meet damage control targets with additional dampers based on the Park damage index.