一种基于增量比例加载的破坏应力修正算法

An Algorithm for Failure Stresses Modification Based on Increment Proportional Loading

针对目前破坏应力修正算法不能适应三维问题的局限性,且国内外许多学者结合堆石坝坝体原型观测资料分析表明,填筑期坝体单元的应力路径接近比例加载,在假设一个计算增量步内材料的力学响应行为满足应力比例加载条件下,提出增量比例加载破坏应力修正算法,与材料破坏一定发生在加载过程中客观事实相一致;可较好地解决三维问题拉、剪破坏应力修正和应力迁移计算问题;在一定程度上还可以自适应跟踪土体破坏时的应力路径,现有平面问题的某些破坏应力修正算法可以视为该算法的特例。

The current failure stresses modification approaches were not suitable for the three dimensional finite element analysis of dam. The observations made by many researchers across the world demonstrate that stress-path of dam element was similar to proportional loading during construction. A new failure stresses modification algorithm was thereby proposed in this research based on the prototype measurement information of rock-fill dam. The algorithm is according with the concept that the failure occurs during loading process, and could be used to calculate the failure stresses due to tension or/and shearing failure. The algorithm was also used to solve the problem of stress migrating, and to some content, can follow adaptively the stress-path of failure. Some existing algorithms for solving plane problems could be considered the simplifying cases of the algorithm presented.