加筋砂土挡墙极限荷载的上限解

Upper Bound Solutions for Ultimate Load of Reinforcedsand Retaining Walls

摘要:

室内模型试验结果表明加筋砂土挡墙的破坏模式可以简化为双楔形体形式.以此为依据,构建了对应破坏模式的速度场.基于传统的塑性极限分析上限定理,考虑面板刚度影响,分别推导了前加载和后加载条件下的加筋砂土挡墙的极限荷载上限解的计算公式,并提出了采用序列二次规划法(SQP)对导出公式进行优化求解的计算方法.利用建议的公式和方法对加筋砂土挡墙的极限荷载上限解进行了系列性的计算,并将计算结果与模型试验结果进行了比较全面的比较.结果表明:利用该上限解计算方法所获得的加筋砂土挡墙极限荷载与模型试验结果一致性良好.另外,所提出的上限解计算方法还可以比较准确地反映加筋层数以及面板刚度变化对加筋砂土挡墙极限荷载的影响.

Abstract:

Model test results show that the failure mode of reinforcedsand retaining walls can be simplified into a twowedge block.Based on the abovemotioned failure mode and the upper bound theorem of classical plasticity theory limit analysis,the upper bound solutions for the ultimate load of reinforcedsand retaining walls under front loading and back loading are derived with a consideration of the effects of facing rigidity.By applying a nonlinear sequential quadratic programming (SQP) algorithm,the proposed upper bound solutions for each analytical expression is optimized for solving.Based on the proposed computational method,a series of the upper bound solutions for the ultimate load of reinforcedsand retaining walls are solved.Results show that the computational solutions agree well with the ultimate loads obtained from the physical model experiments,and the proposed upper bound method can reasonably consider the effect of the reinforced layer numbers and the facing rigidity on the ultimate load of reinforcedsand retaining walls.