不同曲率半径下曲线梁桥的地震时程分析

Seismic time history analysis of curved girder under different radius of curvature

为了分析曲率半径对曲线梁桥抗震性能的影响,以某城市一立交匝道曲线梁桥为背景,针对该匝道曲线梁桥,运用空间大型桥梁有限元分析软件Midas Civil,分别建立了五个不同半径下该曲线梁桥的有限元模型,探索不同半径下曲线梁桥的地震响应。采用E1 Centro地震波,只考虑桥梁的自重作用并采用多方向的地震动输入,进行了地震时程分析,研究了不同曲率半径下的曲线梁桥内力、位移的时程响应,并互相进行了比较,结果显示当自振频率比较小时,无论曲率半径如何变化,桥墩均出现弯扭,并且曲率半径对曲线梁桥的顺桥向和横桥向的地震响应均有较大影响。

In order to analyze the influence of the radius of curve beam bridge seismic performance,taking an overpass ramp curve girder bridge as the background in a city. On the ramp curve girder bridge,by using the space finite element analysis of software Midas Civil,five different finite element model of the curved girder under the radius are established to explore the different radius of the curved girder Bridges under seismic response. The earthquake time history analysis is used with E1 Centro seismic waves and the weight of bridges and multi-direction of ground motion input is taken into account. The different curve radii of curvature of the beam bridge under internal force and displacement time history response are studied,and compared with each other. The results showed that when the natural frequency is relatively small,no matter how the radius of curvature change,piers are bending and torsion occurs,the radius of curvature and have a greater impact on the seismic response curve beam bridge along the bridge and the transverse direction.