基于Hill稳定条件的条形锚板抗拔承载力研究

基于虚功原理的Hill稳定条件可较为明确地判定岩土材料的局部稳定性和整体稳定性:当地基系统的局部二阶功小于0时,材料点局部潜在失稳;当地基的整体二阶功小于0时,地基系统达到极限状态,整体潜在失稳。对ABAQUS进行了二次开发,使Hill稳定条件与有限元法相结合,求解胶结钙质土地基中条形锚板的抗拔承载力。研究结果表明,对于条形锚板在摩擦型岩土材料中的抗拔承载力问题,采用有限元方法结合Hill稳定条件,能较好地预测地基失稳范围和潜在失稳区域,失稳判据明确,易于确定极限荷载,并能较为准确地描述锚板的承载力系数及其随埋深的变化规律。利用有限元法结合Hill稳定条件求解承载力问题的思路和方法是有效和可行的,有明确的物理意义和力学理论基础,应用方便,值得进一步研究、推广并应用于较为复杂的岩土工程问题。

Pullout capacity of anchor plate in cemented soil based on Hill’s stability condition

Based on the secondary development of ABAQUS by the object-oriented program language Python, the finite element method (FEM) with Hill’s stability condition is applied to analyze the bearing capacity of strip anchor in cemented calcareous soils; and the potentially instable regions in the soil are studied accordingly. When the local second order work is negative, some locally instable regions appear in soils; while the global second order work is negative, the system reaches limit state and becomes potentially instable. The limit bearing capacities predicted by the FEM with Hill’s stability condition are close to the theoretical solution. The FEM with Hill’s stability condition can also fairly simulate the potentially instable regions in soils. In general, the FEM with Hill’s stability condition, which has a clear mechanical background, is a convenient method to apply and deserves further study.