非线性无网格伽辽金法的实现

Realization of Nonlinear Element Free Garlerkin Method

提出了应用无网格伽辽金法计算非线性混凝土问题的基本方法.无网格伽辽金法(EFGM)是近些年发展起来的一种数值算法,它采用移动的最小二乘法构造形函数,从能量泛函的弱变分形式中得到控制方程,该法只需节点信息,不需将节点连成单元.在积分网格中,取高斯点的本构关系随应力变化来反映混凝土的非线性性质.文中混凝土的本构模型选用OTTOSEN本构,屈服准则选用修正的莫尔库仑强度准则,通过算例分析,验证了程序的可靠性及应用无网格伽辽金法解决非线性混凝土问题的可行性,表明该方法在混凝土材料领域有着广阔的应用前景.

The basic method of calculating nonlinear problem of concrete by Element Free Garlerkin Method(EFGM) developed in recent years is put forward.EFGM only needs the message of nodes.In this method,shape function is constructed by using Moving Least Square and the control equation is formed by using energy functional analysis and variational priciple.The nonlinear of concrete is reflected by the constitutive relation of Gauss nodes which in integral grid changing with stress.In this paper,OTTOSEN model is selected as the constitutive model of concrete,and amendatory Mohr-Coulomb strength principle is selected as the yield criterion.The calculation shows that the method is feasible and has wide foreground in the field of analysis concrete structure.