加筋土挡墙潜在破裂面模型试验研究

Study on Potential Failure Surface Model of Reinforced Soil Retaining Walls

加筋土挡墙的潜在破裂面为筋带最大拉力点的连线,其合理确定是加筋土挡墙结构设计的关键。现行规范仅对单级直立式加筋土挡墙的潜在破裂面有明确规定,尚无适于不同台阶宽度的加筋土挡墙潜在破裂面的通用计算模式。本文以河龙高速公路加筋土挡墙为原型,对台阶式加筋土挡墙的潜在破裂面进行大尺度模型试验研究,筋带拉力采用自制拉力传感器局部置换测点处的筋条进行测试。以模型试验测试结果和规范采用的0.3H破裂面为基础,利用极限平衡理论和参数分析方法,提出台阶式加筋土挡墙潜在破裂面的实用计算模式。该模式能够适用于不同台阶宽度的加筋土挡墙,当台阶宽度为零时,可退化为0.3H破裂面。

The potential failure surface of the reinforced soil retaining wall （RSRW） is the connection line of the points where layers of reinforcement have the maximal pull, its rational addressing is the pivotal problem for structural calculation of RSRW. The potential failure surface is explicitly specified in the current specifications for the single erective RSRW, but the universal calculation model of the RSRWs with different step widths is lacking. Taking the RSRW of the He-Long Highway as a prototype, the potential failure surface of stepped RSRW was investigated by a large scale model test, the reinforcement pull was measured by a kind of homemade pull sensor. Based on the results of the model test and the 0. 3H failure surface in the current specifications, using the limit equilibrium theory and the parameter analysis method, a practical calculation model of the potential failure surface for stepped RSRW is advanced. This model can be applied to RSRWs with different step widths, if the step width is zero, the failure surface can degenerate into 0.3H.