基于Bui-Quoc.T法则的疲劳寿命可靠性计算方法  

Study on Method for Calculating Reliability of Fatigue Life Based on Code of Bui-Quoc. T

作　　者：郑怡[1,2,3] 李莉[2,4] 刘明[1] 许嘉龙 高飞[3] 

机构地区：[1]沈阳建筑大学土木工程学院,辽宁沈阳110168 [2]辽宁省建筑材料监督检验院,辽宁沈阳110032 [3]重庆交通大学结构工程重点实验室,重庆400074 [4]武汉理工大学材料科学与工程学院,湖北武汉4300701

出　　处：《沈阳建筑大学学报（自然科学版）》2010年第3期507-510,共4页Journal of Shenyang Jianzhu University：Natural Science

基　　金：住房和城乡建设部科技攻关项目(2009-K3-29);沈阳建筑大学结构工程省级重点实验室开放基金项目(JG200705);重庆交通大学结构工程重点实验室2007开放基金项目(CQSLBF-Y07-4);沈阳市科学技术计划项目(1091064-A-00)

摘　　要：目的提出一种新的疲劳寿命可靠性计算方法,为非线性结构疲劳寿命计算提供参考.方法分析Miner准则在进行疲劳损伤累积计算时的不适用性,在此基础上应用Bui-Quoc.T非线性累积损伤法则,以结构疲劳强度持久限的降低作为衡量损伤度的参数,建立了新的非线性累积损伤模型.在此基础上推导出疲劳寿命可靠性计算公式,并采用蒙特卡罗法对其进行计算.结果通过算例计算可靠度指标为4.11,计算结果偏于安全,表明此算法可靠,若采用线性累积算法计算,则无法得到有效结果.结论提出的疲劳寿命可靠性计算方法可用于结构在复杂载荷作用下的疲劳寿命可靠度计算.A new method for calculating reliability of fatigue life is raised in the paper and the reference for computing of non-linear fatigue life is supplied.Basing on the analysis on the inapplicability of code of Miner on computing non-linear fatigue life,the code of Bui-Quoc.T on non-linear accumulate damage is ap-plied,a new nonlinear accumulate damage model is derived from decreasing the lasting limit of structural fatigue strength,which is regarded as parameter of determining the value of damage.Based on this model,a formula of calculating reliability of fatigue life is obtained,and it is computed by means of Mentor-Carlo method.Combining with the test,the reliability index is 4.11,calculating result is safer and the method is reliable.While the linear accumulate algorithm is carried out,effective results can′t be obtained.The result indicates that the method is adaptable to carry on the reliability compution of non-linear fatigue life.The meth-od for calculating reliability of fatigue life can be applied to calculate structural reliability of non-linear fatigue life in complex loading.

关 键 词：疲劳寿命 可靠度 变幅荷载 寿命循环分数 

分 类 号：TU312[建筑科学—结构工程]