研究目的: 挡土墙结构顶部作用集中荷载的工况出现在越来越多的工程建设中。目前国内外普遍将荷载简化为沿墙长方向的均布荷载,按照平面问题进行结构设计。这种简化计算方法往往是通过安全系数进行包络设计,缺乏理论支撑,造成工程浪费的同时也会因为对集中荷载下挡土墙稳定和内力分布考虑不周,给工程建设留下隐患。本文基于有限元软件ABAQUS,建立各类挡墙结构的三维实体模型,模拟集中荷载及均布荷载作用下的内力分布规律,以期得到准确的修正计算方法。
研究结论: (1)可以利用集中荷载作用修正系数调整均布荷载简化计算结果;(2)荷载强度大小对集中荷载作用修正系数没有影响;(3)单一荷载作用下,集中荷载作用增强范围仅与挡墙节长相关,并得到了其计算表达式;(4)得到了几类典型挡土墙结构的修正系数计算表达式;(5)本文得到的集中荷载作用下挡土墙结构内力分布规律以及简便的修正计算方法,可为今后类似荷载工况下的挡土墙设计提供理论支撑和设计参考。

Research purposes: The condition of concentrated load acting on the top of retaining wall structure appears in more and more engineering construction. At present, the concentrated load is generally simplified as uniformly distributed load along the rectangular wall, and the structure is designed according to the plane problem. This simplified calculation method is usually to carry out envelope design by means of safety coefficient, which lacks theoretical support and causes engineering waste, and also leaves hidden danger for engineering construction due to poor consideration of retaining wall stability and internal force distribution under concentrated load. In this paper, based on the finite element software ABAQUS, three-dimensional solid models of various retaining wall structures were established to simulate the internal force distribution law under concentrated load and uniformly distributed load, in order to obtain an accurate correction calculation method.
Research conclusions: (1) The correction coefficient of concentrated load action can be used to adjust the simplified calculation results of uniformly distributed load. (2) The load strength has no influence on the correction coefficient of concentrated load. (3) Under a single load, the intensification range of concentrated load is only related to the length of retaining wall joints, and its calculation expression is obtained. (4) The expressions for calculating the correction coefficients of several typical retaining wall structures are obtained. (5) The internal force distribution law of retaining wall structure under concentrated load and simple correction calculation method obtained in this paper can provide theoretical support and design reference for retaining wall design under similar load conditions in the future.