基于ABAQUS基坑开挖施工对既有桥梁影响的分析

发布时间：2018-06-17 03:33

本文选题：基坑开挖 + 桥梁　；参考：《天津大学》2014年硕士论文

【摘要】：随着我国高速铁路的快速建设,越来越多的高速铁路投入运营。高速铁路因舒适快捷,已成为人们选择出行的首要交通工具;正因为如此,其安全运行也至关重要。目前已经开通运营的高速铁路中桥梁占线路的相当份额。所以高速铁路桥梁附近的施工成为工程界必须考虑的问题,而基坑开挖势必会对既有高速铁路桥梁的正常运营产生影响。基坑开挖引起土体位移会对群桩高速铁路梁桥产生诸多不利影响:第一,土体的水平位移导致桩身变形,进而引起桥面水平位移;第二,土体竖直位移引起桩基竖直位移进而引起桥面竖直位移;第三,各桥墩和桩基间由承台和上部结构相互连接彼此之间产生复杂作用,更加难以估计其变形。本文结合工程实际,应用有限元软件ABAQUS对某高速铁路桥附近基坑开挖进行三维有限元模拟,并分析其桩、墩沿深度方向的水平侧移、墩顶水平位移和竖直位移。其次,鉴于三维分析中复杂的建模过程、较高的硬件配置要求和较长的计算时间,本文提出了二维有限元简化方法,并分别进行弹塑性分析。通过三维模型分析结果和二维模型分析结果进行对比分析,再对不同工况进行对比分析。经过对比二维简化方法可用于工程实际的数值分析。然后对基坑开挖的影响因素的各工况进行二维有限元分析,分别分析不同基坑开挖深度、基坑开挖宽度和基坑与既有桥梁的距离对既有桥梁产生的桩、墩沿深度方向的水平侧移、墩顶水平位移和竖直位移的影响。最后对不同基坑开挖方式进行二维有限元模拟,分析不同基坑开挖方式各工况的既有桥梁产生的桩、墩沿深度方向的水平侧移、墩顶横向位移和竖直位移。通过对三维有限元模拟和二维有限元模拟进行对比,对类似工程的数值模拟进行计算方法的指导;通过对各影响因素的分析和对不同基坑开挖方式各工况的对比,为实际施工方案的确定提供有意义的指导。
[Abstract]:With the rapid construction of high-speed railway in China, more and more high-speed railways are put into operation. High-speed railway has become the most important vehicle for people to travel because of its comfort and speed, and because of this, its safe operation is also very important. At present, the high-speed railway has been opened, bridge accounts for a considerable share of the line. So the construction near the high-speed railway bridge must be considered in the engineering field, and excavation of foundation pit will inevitably affect the normal operation of the existing high-speed railway bridge. The soil displacement caused by excavation of foundation pit will have many adverse effects on the beam bridge of high-speed railway with group piles: first, the horizontal displacement of soil will lead to the deformation of the pile body, and then cause the horizontal displacement of the bridge deck; second, The vertical displacement of soil causes vertical displacement of pile foundation and then causes vertical displacement of bridge deck. Thirdly, the pile pier and pile foundation are connected with each other by cap and superstructure, so it is more difficult to estimate their deformation. In this paper, the finite element software Abaqus is used to simulate the excavation of foundation pit near a high-speed railway bridge. The pile, the horizontal displacement of the pier along the depth, the horizontal displacement of the pier top and the vertical displacement are analyzed. Secondly, in view of the complex modeling process, high hardware configuration requirement and long calculation time in 3D analysis, a two-dimensional finite element simplified method is proposed, and elastic-plastic analysis is carried out respectively. The results of three-dimensional model analysis and two-dimensional model analysis are compared and analyzed. By comparing the two-dimensional simplified method, it can be used in the numerical analysis of engineering practice. Secondly, the influence factors of excavation are analyzed by two-dimensional finite element method, and the piles produced by different excavation depth, excavation width and the distance between foundation pit and existing bridge are analyzed respectively. The horizontal displacement of the pier along the depth direction and the influence of the horizontal displacement and vertical displacement on the top of the pier. Finally, two dimensional finite element simulation of different excavation methods is carried out to analyze the piles produced by existing bridges in different excavation modes, the horizontal lateral displacement of piers along the depth direction, the lateral displacement of the pier top and the vertical displacement. Through the comparison of three-dimensional finite element simulation and two-dimensional finite element simulation, the numerical simulation of similar engineering is guided by the calculation method, and through the analysis of various influencing factors and the comparison of different excavation modes and working conditions, To provide meaningful guidance for the determination of actual construction plan.
【学位授予单位】：天津大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TU753;U442

【引证文献】