张承高速高边坡稳定性离散元模拟研究

Discrete Element Numerical Simulation on Stability of High Slope in Zhangjiakou-Chengde Expressway

以张承高速某高边坡工程为依托,采用单轴压缩模拟试验标定出边坡各岩土层的细观参数,建立边坡的离散元模型,分析了边坡的稳定状态,并对边坡的失稳过程进行了研究。结果表明:粉土层向下滑动,并在坡脚堆积,圆砾层未发生滑动。模型中出现的裂纹主要在粉土层。边坡的破坏过程如下:首先粉土层颗粒在重力作用下黏结被破坏,由于粉土层底部颗粒先滑出坡面,使中上部颗粒失去支撑而发生大规模滑动。基于上述分析,建议对边坡开挖后采取锚索或土钉进行支护,同时对坡面采用水泥砂浆防护等加固措施。

Based on a high slope on Zhangjiekou-Chengde Expressway,the micro-parameters of each geotechnical layers are determined through uniaxial compression simulation test.Discrete element model of slope is established,and analysis of slope stability is made,and instability process of slope is recorded.The results show that silty layer slips down and deposit at the foot of the slope,and slide is not observed in the round gravel layer.Cracks mainly appear in the silty layer of the model.The failure process of the slope is as follows：the cohesion in the silt layer is destroyed due to gravity,and grains＇spilling out of the slope surface leads to the medium and upper grains sliding downwards due to loss of support.Based on the analysis above,the conventional support measures such as anchor cable or soil nailing should be taken,and in the meantime the cement mortar should be used for reinforcement.