通常加筋土挡墙筋材拉力和锚固区长度的设计计算是基于莫尔-库仑准则得到的,没有考虑中主应力σ2的影响,而双剪强度理论克服了莫尔-库仑准则的不足,并利用双剪强度理论的φ1,Ct参数替代莫尔-库仑抗剪强度指标。基于双剪强度理论(m=1)计算分析了挡墙筋材拉力大小及其锚固区长度,并将该结果与基于莫尔-库仑准则计算的结果进行了对比,结果表明墙高较小时两者结果基本一致,而墙高较大时,双剪强度理论计算结果大于莫尔-库仑准则计算的结果。
Generally, the tension and anchorage length of geotextile are calculated based on Mohr-Coulomb strength theory, and the intermediate principal stress is not taken into account. The influence of intermediate principal stress can be considered with twin shear theory, and the parameters of Mohr-Coulomb strength theory (φ0, c0) are modified with the twin shear strength parameters (φ1 , c1 ). Based on the twin shear theory, the tension and length of geotextile are modified. The example shows that the tension and anchorage length of geotextile with twin shear theory( m = 1 ) is close to that with Mohr-Coulomb strength theory when the wall height is small: while upon a further increase in wall height, the tension and anchorage length of geotextile become bigger than those calculated by MohrCoulomb strength theory.