土钉支护有限元分析

Finite Element Analysis of Soil Nailing

土钉支护是目前应用最广泛的基坑支护型式之一。如何考虑土钉支护的作用至今仍存在值得探讨的问题。采用有限元方法对土钉支护的作用机理、变形及内力进行分析,其接触界面节理单元采用改进的四结点Good-man无厚度单元,土体本构关系为能反映土体剪胀性和扩容性的Drucker-Prager准则,并将其应用于工程设计中。与实际监测结果的对比验证可以看出,该模型是有效性和可行的。研究结论对土钉支护的设计与施工有较高的应用价值。

Soil nailing is one of the support pattern widely used today. It is useful to discuss the problem of the mechanism of soil nailing. The mechanism of action, deformation and stress state of the soil nailing were analyzed by using the finite element method. In the finite element model, the modified Goodman Jointed Element was adopted to simulate the interface between the steel bar and the rock or soil medium, and the Drucker-Prager rule which reflects the Shear-Swell performance of the soil was adopted in the model, too. The comparison between monitoring results and inspecting in practical engineering examples shows that the soil nailing model is very effective and feasible, which turns out to meet the design requirements completely and has a wide application value in the design and construction in the soil nailing.