罕遇地震下空心薄壁高墩大跨T形刚构桥弹塑性地震反应分析

利用大型结构分析软件建立了空心薄壁高墩大跨T形刚构桥的空间抗震有限元模型,运用非线性动态时程反应方法进行了高烈度地震区罕遇地震作用下的弹塑性地震反应计算,并与线性时程法和反应谱法的计算结果进行了对比.同时对该结构的延性抗震性能进行了分析评价.结果表明空心薄壁高墩T形刚构铁路桥在罕遇地震下处于较弱的非线性受力状态,其受到的损伤仍然很小,具有较好的抗震能力,结构考虑非线性塑性反应后的地震力与弹性相比明显减小.

Elastic-plastic Seismic Response Analysis of Hollow Thin-walled High-pier Large-span T-Shaped Rigid Frame Bridge under High-Level Earthquake Conditions

By using structure analysis software,a finite element model of a hollow thin-walled high-pier and large-span T-shape rigid frame bridge is built for seismic analysis.The elastic-plastic seismic response is calculated by using the nonlinear dynamic time-history response method for high-level earthquakes in high-intensity seismic regions.The results are compared by using the linear time-history and response-spectrum methods.The seismic ductility performance of the hollow thin-walled high-pier structure is also analyzed and evaluated.It is concluded that the hollow high-pier thin-walled T-shaped rigid frame railway bridge is in weak nonlinear state under high-level earthquake conditions;however,the damage is small,as it has good seismic-resistant capability.Compared with the elastic seismic response,the seismic forces experienced by the structure are significantly reduced in the nonlinear plastic response.