基于多点激励动力模型的支承体系斜拉桥行波效应分析

Traveling Wave Effect Analysis of Cable-stayed Bridge with Support System Based on More Incentives Dynamic Model

研究目的:地震激励的输入是大跨度桥梁结构抗震设计中最薄弱的环节。大跨度桥梁结构由于基础间间距较大,进行地震响应分析时应考虑行波效应的影响。目前,国内对于支承体系斜拉桥行波效应影响规律的研究成果并不多见。该文基于大型有限元分析软件MIDAS/CIVIL计算平台,较为准确地模拟了地震波对郑州市中心区跨铁路斜拉桥基础不同位置的激励差异,分析比较了该桥在不同波速地震波作用下的行波效应,对该类桥型地震响应行波效应的一般影响规律进行了讨论。研究结论:在一定的相位差范围内,考虑地震波的各单向行波效应和三向正交行波效应时,结构的内力与位移均呈周期性变化,并且变化周期与桥梁自振周期基本一致。同时,行波效应对支承体系斜拉桥地震响应峰值存在显著影响。

Research purposes ： Importation of the earthquake incentives is the weakest link for seismic design of large - span bridge structure. As the greater distance between basis of the large - span bridge structure, traveling wave effect should be considered in the progress of earthquake response analysis. At present, the law of the research on traveling wave effect for cable - stayed bridge with support system is rare in domestic. Based on the large - scale finite element analysis software MIDAS / CIVIL computing platforms, a more accurate simulation for the seismic waves on the basis of the cable - stayed bridge spanning railway in center of Zhengzhou differences under the different locations incentive has been performed in this paper, as well as analysis and comparison of the wave traveling wave effect when the bridge be at different velocity of the seismic, a general discussion on traveling wave effect of this bridge - type has been achieved. Research conclusions：In a certain phase difference, when considering the one - way trip to the wave effect and three orthogonal traveling wave effect, internal forces and displacement of the structure both change cyclically, with natural cycle the same basically. At the same time, traveling wave effect results a significant impact on the response peak to the earthquake for the cable -stayed bridge with support system.