为了研究网格状带齿加筋砂垫层结构筋土界面的细观作用机理, 利用颗粒流程序, 采用内置 clump 方法开发了可模拟砂土性状的椭圆形颗粒, 建立了筋土拉拔试验的数值模型. 与室内试验结果进行对比, 分析了拉拔界面剪切带的演变与荷载传递机理. 结果表明: 在拉拔过程中, 齿筋附近出现应力集中现象; 相同的拉拔位移下, 带齿加筋砂垫层体中的剪切带厚度明显大于加筋黏土体中的剪切带厚度, 且剪切带的形状也发生了明显改变; 齿筋的贡献度随拉拔位移的不同而有所差异, 且每根齿筋的贡献度也不一致.

To investigate the micro-mechanism of interaction between denti-inclusions and sand cushion, elliptical group particles were developed. Numerical simulation of pull-out tests was performed by PFC2D. The model was validated by comparing the numerical results and the pull-out test results. Evolution of the shear band and load transfer mechanisms was studied. The results show that the stress concentration occurs near denti-inclusions, and the upper and lower interfaces are not symmetrical. The shear bond's thickness of sand cushion reinforced with denti-inclusions is significantly larger than clay reinforcement in case of the same pullout displacement. Every denti-inclusion has a different rate of contribution to pull-out force and change when drawing.