关于多跨门式刚架桥的优化方法研究

Research on optimization method of multi span portal rigid frame bridge

多跨门式刚架桥具有复杂的结构力学特点,影响结构内力的因素较多,边墩及基础为结构设计的控制节点。本文通过建立不同桩基布置形式、不同墩高、设置承台偏心的多跨门式刚架桥有限元模型,进行结构分析并总结受力特点,归纳刚度分配,内力传递等不同效应。研究表明:根据不同的地质条件,桥跨要求,调整桩基布置和墩高,适当设置承台与桥墩的偏心距离能够有效优化设计,降低边墩基础的桩基配筋,对结构受力更加有利。

The multi span portal rigid frame bridge has complex structural mechanics characteristics,and there are many factors affecting the internal force of the structure.The side piers and the foundation are the control nodes of the structural design.In this paper,the finite element model of multi span portal rigid frame bridge with different pile foundation layout,different pier height and eccentric bearing platform is established to analyze the structure and summarize the stress characteristics,summarize the difierent effects of stiffness distribution and internal force transmission.The results show that:according to different geological conditions and bridge span requirements,adjusting the pile foundation layout and pier height,setting the eccentricity distance between pile cap and pier properly can effectively optimize the design,reduce the pile foundation reinforcement of side pier foundation,which is more beneficial to the structural stress.