大跨度连续梁桥的地震碰撞模拟分析

Collision Simulation Analysis of the Bridge under the Seismic Action

摘要: 本文通过对于一座大跨度连续梁桥地震碰撞过程的模拟分析和数据显微处理，首次发现并提出了碰撞群的概念，认为碰撞群中高频高强的加载卸载过程(可称之为冲击钻效应)是导致碰撞破坏的原因。在此基础上，本文提出了一种梁端碰撞损伤度评估方法，并针对本文的研究对象给出了碰撞损伤度评估结果。本文还通过对比大桥不同模型(不同墩高、不同基础类型)中所发生的地震碰撞，提出：1) 为减轻多跨连续梁桥地震碰撞、降低边跨落梁概率，应合理设置和设计制动墩；2) 在建模时，梁墩基础的模拟方式应谨慎、合理；3) 在高烈度区进行高墩大跨度连续梁的桥台设计时，应考虑碰撞中的冲击钻效应所。

Abstract: In this paper, with a large span continuous girder bridge as the research object, the simulation analysis of seismic collision and the data microprocessing is carried out. based on this, a new the concept of the collision group was first discovered and put forward. Just because of the loading and unloading process in high-frequency and high-strength happened in a collision group (can also called impact drill effect), the collision damage is resulted. On this basis, we propose a beam end collision damage evaluation method and by applying the evaluation method on to the large span continuous girder bridge, the results of the assessment of the degree of collision damage is given. In this paper, by contrast seismic collision occurred in different models of bridge (with different pier, different base types) , the following suggestions should be pay attention: 1) To mitigate multi-span continuous girder bridge seismic collision, reducing side span girder falling probability, the setting and the design of a brake pier should be reasonable; 2) When set up the model of a bridge, how to simulating the base of pier should be cautious and reasonable; 3) When designing a long span continuous beam bridge with high pier in the high-intensity area, the impact drill effect should be considered.