顺层滑坡弹塑性接触有限元稳定性分析

ELASTOPLASTIC CONTACT FEM ANALYSIS OF BEDDING LANDSLIDE STABILITY

有限元强度折减法可以作为极限平衡分析方法的一种逆过程。根据已有文献报道和工程实践,建立有限元强度折减法与极限平衡法计算稳定性系数的数理统计相关式,为充分利用极限平衡法计算滑坡稳定性系数的优点、发挥有限元强度折减法计算滑坡稳定性系数的优势和保证滑坡稳定性系数计算及分析的可靠性提供更加充分的依据。确定有限元强度折减法中滑体(包括滑带)的强度参数和重度、精确划分网格和收敛准则等原则。通过工程实例分析认为,这些原则的确定在风化岩质顺层滑坡稳定性系数计算及稳定性分析中是正确的,可作为该类型滑坡稳定性分析和计算的参考。采用不分离接触弹塑性有限元强度折减法分析高度非线性问题的风化岩质顺层滑坡稳定性,可以更加逼真地反映滑坡变形、破坏的实际情况。

Contact FEM strength reduction method is an inverse process in limiting equilibrium analysis of slope stability. Based on the results of reported documents and engineering practice, correlations between nonlinear FEM strength reduction analysis and limiting equilibrium analysis of slope stability are established. The result lays more sufficient foundation for making full use of the advantages of both methods above in the analysis of slope stability; and it guarantees the reliability of calculation of the safety factor and analysis of slope stability. The principles of determining strength parameters of slide mass and glide, density of slide mass, meshing accurately finite element, and determining convergence criteria are established. According to analysis of engineering concrete example, it is testified feasibly in the analysis of slope stability and the calculation of the safety factor. Therefore, it may act as a reference to the analysis and calculation of the similar landslide. The stability of decomposed-rock bedding slope with high nonlinear problem is analyzed by FEM strength reduction of non-separation contact elastoplastic model, which may more clearly reflect actual state of slope deformation and failure.