公路连续梁桥体结构抗震性能数值模拟

Numerical Simulation of Seismic Performance ofHighway Continuous Beam Bridge Structure

为研究公路桥梁在复杂地震作用下的抗震特性,以稿吾卡1号大桥工程为研究案例,使用有限元软件分析了桥梁的自振特性,得到了地震作用下桥体的自振特性、位移分布与内力特征,并提出了对应的安全控制建议,研究结果表明:桥梁结构整体振动特性基频为0.8 Hz附近,振型中以纵向振型居多,桥梁上部的横向振动较为明显,将会导致桥梁上部有较大的横向位移,需要引起足够重视。梁内轴力自左向右逐渐增大,到设固定铰支座的2号墩达到最大,然后又逐渐变小,与桥型本身结构特点较为一致。反应谱分析计算的结果动态时程法分析的结果大,而且后者普遍是前者的78%左右;并提出了对应的安全控制建议,保证了桥梁抗震要求。

In order to study the seismic characteristics of highway bridges under complex earthquakes,This article takes the Gaowuka No.1 Bridge project as a case study,uses finite element software to analyze the natural vibration characteristics and seismic response time history of the bridge,and puts forward corresponding safety control suggestions.The research results show that:the fundamental frequency of the overall vibration characteristics of the bridge structure is about 0.8 Hz,and the transverse vibration of the upper part of the bridge is more obvious,which will lead to a large transverse displacement of the upper part of the bridge,which needs to be paid attention to.The axial force in the beam gradually increases from left to right,reaches the maximum at Pier No.2 with fixed hinge supports,and then gradually decreases,which is more consistent with the structural characteristics of the bridge itself.The results of response spectrum analysis are generally larger than those of dynamic time history analysis,and the latter is generally about 78%of the former.The corresponding safety control suggestions are put forward to ensure the seismic requirements of the bridge.