岩石应变软化弹塑性有限元分析

本文从岩石的变形特性和界面约束理论出发,建立了应变软化规律及共有限元本构方程。这种方程的求解存在着解法难与收敛慢和漂移界面的两个问题。解决方法:(1)分析各种解法,采用初应力法,并进行改进称之改进的初应力法,以加速其收敛;(2)考查各种漂移界面的修正方法,选取其中较好的一种。编制了一个相应的EPSF程序,并对金川某巷道进行了软化有限元分析。

Finite Element Analysis of Elastoplastic Rock with Strain-softening

Based upon rock deformation characteristics and bounding surface model, a strain-softening law and its constitutive equation are established. In the equation, two difficult problems on solution and surface drifting are existed. First, after numerical approaches to softening problem were evaluated, an initial stress method is employed and then improved. It is called improved initial stress method which accelerate convergence. Secondly, various surface drifting updatings are compared and a good correction is selected. Correspondingly, the program called EPSF is developed. Finally a strain-softening analysis to a tunnel in Jinchuan is given.