Sensitivity of probabilistic fracture mechanics analysis to variations in statistical parameters

作     者：Sprung, I. 

作者机构：415 Erin Rd Stoughton MA 02072 USA 

出 版 物：《THEORETICAL AND APPLIED FRACTURE MECHANICS》 (理论与应用断裂力学)

年 卷 期：2007年第48卷第3期

页      面：231-237页

核心收录：

学科分类：08[工学] 0802[工学-机械工程] 0801[工学-力学（可授工学、理学学位）] 080102[工学-固体力学] 

主　　题：Probabilistic fracture mechanics Statistical parameters Surface crack Sensitivity 

摘      要：Probability of failure (p(f)) of a structure is usually calculated for a specified set of statistical parameters (mean, standard deviation, and probability distribution) that characterize random variables. This approach may not be efficient in cases where one would like to know the effect of variations in statistical parameters on the probability of failure. A method based on generating and analyzing randomly selected statistical parameters is proposed. The method consists of generating data-bases of mean and coefficient of variation (COV = mean/standard deviation) values of relevant fracture mechanics variables through a random process. The method was applied to surface cracks in a flat wide plate loaded under elastic conditions. Probability of failure was calculated for each database record using the first-order reliability method (FORM). Multiple linear regression analyses of the database records were performed with p(f) as dependent variable and statistical parameters as independent variables. The predicted p(f) values were in very good agreement with the directly calculated p(f) values for the specified variations of statistical parameters (+/- 10%, +/- 15%, and +/- 20%), except those for fracture toughness and tensile stress, where variations should be limited to +/- 10% and +/- 15% ranges. (C) 2007 Elsevier Ltd. All rights reserved.