挡土墙后双层黏性土的主动土压力计算

针对挡土墙墙后为双层黏性土的情况,提出一种可靠的土压力计算方法.在平面滑裂面假设下,考虑填土黏聚力及填土与挡土墙墙背接触面上的黏着力,推导出双层填土的挡土墙主动土压力关于滑裂面倾角的计算表达式.在单层填土条件下将公式退化对比,表明该方法同样适用于单层填土的工况.通过算例将该方法的计算结果与工程实测值及分层法计算结果进行分析对比,结果表明,该方法的计算结果与实测值较符合.当填土为无黏性土时,可以采用改进分层法计算土压力；当墙后填土为黏性土时,改进分层法计算误差较大,建议采用该方法.

Active earth pressure on retaining wall with multiple layer of cohesive backfill

A reasonable method was proposed to calculate active earth pressure on retaining wall with multiple layer of cohesive soil. Based on sliding plane hypothesis, a formula was derived for the calculation of active earth pressure on retaining wall with multi-layered cohesive soil considering the cohesion force on sliding plane and the adhesive force on interface of backfill and retaining wall. The formula can also calculate the active earth pressure on retaining wall with homogeneous backfill. The calculation results of the present study were compared with that of improved layer method and measured value, and the results accorded well with the measuring results. The active earth pressure acting on retaining wall with granular soil can be calculated by the method of layer analysis, whereas, it is suggested to adopt the proposed method to calculate the active force with cohesive soil.