无粘性土的室内试验和数值模拟

THE INDOOR EXPERIMENT AND NUMERICAL SIMULATION OF COHESIONLESS SOIL

通过室内模型砂槽的试验和GEOSTUDIO模拟,研究了均质无粘性土流土的破坏由开始到结束的过程。通过对试验得到的数据和GEOSTUDIO模拟得到的数据进行对比分析,发现模拟得到的结果与实验得到的结果基本一致,误差在允许的范围内。同时研究表明:均质无粘性土在渗流作用下发生渗透变形的过程中,有一个渗透系数基本不变的阶段。这一阶段土体中还没有形成渗流通道,土体处于暂时稳定的安全渗流状态。超过水力梯度的临界点以后,土体的渗透系数会急剧增加,渗流流量和渗流流速迅速变大,破坏速加快。

Through the indoor model of sand tank experiment and GEOSTUDIO simulation,this paper studies the failure process of homogeneous cohesionless soil flow,from the beginning to the end.Comparative analysis through the test data and the data obtained from GEOSTUDIO simulations,it finds that the simulated results and the experimental results are basically consistent,with the error in the allowable range. At the same time,research shows that the homogenization process without seepage deformation of clayey soil takes place under the action of seepage,and there is a basic invariant phase permeability coefficient. Has not formed the seepage channel at this stage in the soil,the soil is in a safe state is temporarily stable seepage. After the critical point more than hydraulic gradient,soil permeability coefficient will increase dramatically,then seepage flow and seepage velocity changes rapidly together with the destruction of speed.