中承式钢管混凝土拱桥地震动响应分析

Seismic response analysis of half-through concrete filled steel tubular arch bridge

近年来,钢管混凝土拱桥由于具有承载力高、跨越能力强、抗震性能好、施工方便等优点得到广泛应用。以某跨度为240 m的中承式钢管混凝土拱桥为背景,采用Midas/Civil 2013建立桥梁空间有限元模型。采用子空间迭代法计算桥梁前90阶的自振特性,包括频率、周期及振型。桥梁的第一阶频率为0.347 Hz,周期为2.882 s,振型表现为拱肋正对称横弯。同时,采用时程分析法进行地震动响应分析,分析成果可为桥梁健康监测系统在传感器布置和现场动力测试等方面提供依据。

In recent years,the concrete filled steel tubular arch bridge has been widely used due to their high bearing capacity,strong spanning ability,good seismic performance and convenient construction.Based on a half-through concrete filled steel tubular arch bridge with 240 m span,the finite element model of the bridge is established using Midas/Civil 2013.The subspace iteration method is used to calculate the 90-order natural vibration characteristics of the bridge,including frequency,period and vibration mode.The first-order frequency of the bridge is 0.347 Hz,and the period is 2.882 s.The vibration mode is characterized by a symmetric rib transverse rib.At the same time,the seismic response analysis is carried out by time history analysis.The analysis result can provide a basis for the bridge health monitoring system in terms of sensor layout and site dynamic tests.