中卫V撑连续刚构组合拱桥地震响应分析

Seismic Response Spectrum Analysis of Continuous Combined Beam and Arch Rigid Frame Bridge with V-shaped Pier in Zhongwei Bridge

介绍了中卫V撑拱桥三维有限元模型的建立和拱桥的设计与模态分析,并进行了地震反应分析.模态分析表明,各阶振型频率呈现出密集分布的形态,拱的振动出现的较早,反映出这种刚性系杆柔性拱的振动特点.地震反应分析可知,只有桥墩是地震反应的控制构件,故桥墩按地震内力控制设计,其余构件均按组合Ⅲ内力控制设计.当发生8度地震时,该桥的安全性可以得到保障.

A 3-dimensional finite element model and seismic response analysis of an arch bridge are introduced. The results of the mode analysis show that the mode frequencies distribute densely and the vibration of the arch appears relatively earlier. This reflects the vibratory characteristic of rigid tie and flexible arch bridge. The seismic response analysis indicates that the pier is the only control member, so the pier has been designed according to the seismic force,and the others have been designed according to the load combination Ⅲ. The design is assured as a safe arch bridge under the condition of earthquake intensity 8.