计算力学学报Issue(1)：118-122,5.DOI:10.7511/jslx201501020
基于 P-S-N 曲线的强度退化随机模型
Stochastic model of strength degradation based on P-S-N curve
摘要
Abstract
In general,strength degradation is a stochastic and irreversible process.Gamma process is an in-dependent nonnegative increment process which can be used to describe the characteristics of strength degradation.However,during strength degradation process,the degradation data that characterizes de-generate state (wear,crack,corrosion,etc.)is often difficult to measure directly,which is the typical missing data.But the P-S-N curve that characterizes material fatigue performance is generally easy to obtain.Therefore,this paper assumes that the shape parameter of Gamma process is a linear function, and estimates the characteristic parameters of Gamma process using material P-S-N curve.Then a stochastic model of strength degradation based on P-S-N curve is established.Finally,the validity of the proposed model is verified and analyzed by using the fatigue test data of 20CrMnTi steel.The results show that this model can effectively describe the macroscopic trend of material strength degradation.关键词
强度退化/Gamma 过程/P-S-N 曲线/参数估计Key words
strength degradation/Gamma process/P-S-N curve/parameter estimation分类
通用工业技术引用本文复制引用
安宗文,高建雄,刘波..基于 P-S-N 曲线的强度退化随机模型[J].计算力学学报,2015,(1):118-122,5.基金项目
国家自然科学基金(51265025)资助项目 （51265025）
