拟牛顿法求解堆石坝结构非线性方程

Application of Quasi-Newton Method to Nonlinear FEM Equation of Rockfill Dams

探讨了求解堆石坝结构非线性方程的拟牛顿法，详细阐明了拟牛顿法在堆石坝结构分析中的实施过程，并编制了相应的三维非线性有限元分析程序，将拟牛顿法与中点增量法同时用于实例计算，表明拟牛顿法收敛速度较快且数值稳定性好，优越于中点增最法。

he quasi-Newton method,one of solving methods for noninear FEM equation of rockfill dams,is discussed and the practive process of quasi-Newton method in stucture analysis of rockfill dams is also described in detail.A corresponding FEM program for 3-D material nonlinear analysis is developed,Stress and strain of a rockfill dam are calculated by both the quasi-Newton method and the middle point incremental method. Through comparision and analysis, the conclution is drawn that the quasi-Newton method is better than the middle point incremental method.The calculating process shows that quasi-Newton method has better convergence rate and numerical stability and is one of the most successful nonlinear solving methods.