【摘要】 以极限分析下限法理论为基础,利用应力型有限元法建立满足条件的静力许可应力场,将地基的极限承载力问题归结为一个非线性数学规划问题。依据几何上的相似性,引入二阶锥形规划方法,采用预示校正内点法,避免屈服准则(Mohr-Coulomb)顶点约束的线性化近似,实现下限法数学模型的求解。并以均质土体的刚性条形基础的极限荷载为算例,比较了所得数值解与理论解,论证了该法的正确性和有效性。更多还原

【Abstract】 Based on the lower bound theorem in plasticity,a statically admissible stress field was constructed by stress-type finite element method.The formulation of limit analysis on bearing capacity of strip footings led to an optimization problem with a large number of cone-shaped yield restrictions.As an analogous formulation,the predictor-corrector method,an algorithm for second order cone programming(SOCP),was used to tackle the resultant nonlinear programming problem.In SOCP algorithm based on the interior-point method,it was no need to smooth the yield surface in the vicinity of the apex.A numerical example of the ultimate bearing capacity of a rigid strip footing in homogeneous soil was presented to illustrate the validation and effectiveness of the present method with the comparison between numerical lower bound analysis and analytical solutions.更多还原