地基承载力的有限元计算及其在桥基中的应用

有限元强度折减法在边坡稳定性分析中的应用已取得了一定的成果, 但在地基承载力稳定分析中是否适用尚不得而知。本文采用有限元分析软件ANSYS求得了无重土地基的极限承载力, 并与传统的Prandtl解进行了对比, 两者误差在5%以内, 且其滑移线与Prandtl解相近, 说明了采用有限元法求解极限荷载是准确可靠的。文中详细列出了两种方法得到的塑性区和滑移线的异同点。进一步应用于桥基承载力安全系数的计算, 并与经验解进行了比较。

FINITE ELEMENT ANALYSIS FOR THE BEARING CAPACITY OF FOUNDATIONS AND ITS APPLICATION IN BRIDGE ENGINEERING

The shear strength reduction technique has a number of advantages over the method of slices for slope stability analysis. The Finite Element Method (FEM) strength reduction based on the approach has been proved to be suitable for slope engineering. It is still unknown,however,whether the method is applieable for the bearing capacity of foundations.For weightless foundation soil, the ultimate bearing capacity calculated by the proposed method is compared with the classical Prandtl solution.The error is less than 5%, and the slip surfaces given by the two methods are close. The proposed method is employed to calculate the safety factor of the bearing capacity of a real-world bridge foundation,and the results are compared with empirical solutiens.