结构可靠性指标计算的旋转梯度算法  

Rotation gradient algorithm for calculating structural reliability index

作　　者：杨杰[1] 赵德有[1] 

机构地区：[1]大连理工大学船舶工程学院,辽宁大连116024

出　　处：《大连理工大学学报》2011年第2期221-225,共5页Journal of Dalian University of Technology

摘　　要：结构可靠性指标计算是结构可靠度理论重要内容之一.在极限状态曲面非线性程度较高时,一次二阶矩算法经常不能收敛.为此提出了一种求解结构可靠性指标的旋转梯度算法.该算法以HL-RF算法为基础,迭代方向由迭代点处的负梯度方向与上一步迭代方向的线性组合确定.数值算例结果表明,该算法迭代格式简单,具有较强的适应性,即使极限状态曲面非线性程度很高,也能保证算法的收敛与稳定.Computation of the structural reliability index is one of the important factors in structural reliability theory.First-order second-moment algorithm often behaves discretely when the limit state surface is highly nonlinear. So rotation gradient algorithm is presented for computing the structural reliability.The method is based on Hasofer-Lind Rackwitz-Fiessler（HL-RF） algorithm,whose direction vector is determined by the linear combination of the negative gradient direction and former iteration direction vector.The numerical results show that the rotation gradient algorithm possesses the advantages of simplified iteration format and high convergence robust.The algorithm can ensure convergence and stability even the limit state surface is highly nonlinear.

关 键 词：可靠性指标 一次二阶矩 旋转梯度 收敛 

分 类 号：TU311[建筑科学—结构工程]