独塔双索面混凝土斜拉桥抗震性能研究

Seismic performance of concrete cable-stayed bridge with single tower and double cable planes

以某独塔双索面混凝土斜拉桥为工程实例,采用有限元分析程序Midas Civil,基于空间梁单元建立三维有限元模型。采用非线性时程反应法对独塔双索面混凝土斜拉桥进行地震反应分析。该桥分别采用100 a超越概率10%和100 a超越概率2%的两种地震水平时程,每种地震水平时程均采用3组实际强震记录,计算结果取3组中的最大值,地震的激励方向采用“纵向+竖向”和“横向+竖向”两种组合输入方式。研究结果表明:地震作用下该桥的桥墩及主塔各典型截面均处于弹性工作状态,该桥的抗震性能较好。

Taking a concrete cable-stayed bridge with single tower and double cable planes as an engineering example,a three-dimensional finite element model is established based on the spatial beam element by using the finite element analysis program Midas Civil.The nonlinear time history response method is used to analyze the seismic response of concrete cable-stayed bridge with single tower and double cable planes.The bridge adopts two kinds of seismic horizontal time histories with 100-year transcendence probability of 10%and 100-year transcendence probability of 2%respectively.Each kind of seismic horizontal time history adopts three groups of actual strong earthquake records,and the calculation results take the maximum of the three groups.The earthquake excitation direction adopts two combined input modes of"longitudinal+vertical"and"transverse+vertical".The research results show that the typical sections of the pier and main tower of the bridge are in elastic working state under earthquake action,and the seismic performance of the bridge is good.