钢吊车梁疲劳设计可靠指标及分项系数研究  

Reliability index and partial factors for fatigue design of steel crane girders

作　　者：潘春宇[1,2] 童乐为[1,2] 

机构地区：[1]同济大学土木工程防灾国家重点实验室,上海200092 [2]同济大学土木工程学院,上海200092

出　　处：《建筑结构学报》2016年第7期82-88,共7页Journal of Building Structures

基　　金：国家自然科学基金面上项目(51478334;51078291)

摘　　要：定义了钢结构疲劳失效极限状态,基于已有的对钢吊车梁的研究和现场对中级工作制钢吊车梁的疲劳荷载效应实测,分析了疲劳强度和疲劳荷载效应的统计参数,应用一次二阶矩方法计算了疲劳可靠指标,研究了疲劳可靠度设计分项系数的取值。研究结果表明：钢吊车梁中12类细部构造（含应力比影响）的疲劳强度标准差取值范围在0.0251-0.0792之间,当等效应力幅服从对数正态分布时,等效应力幅的标准差为0.0148。为此,建议疲劳可靠指标取值2.9,疲劳强度分项系数取值1.0,疲劳荷载效应分项系数取值1.14。The definition of fatigue failure limit state for steel structures was given. The statistical parameters of both fatigue strength and fatigue load effect were analyzed on the basis of both literature investigation and site tests for fatigue load effect of steel crane girders. First-order second-moment method was used to calculate the fatigue reliability index. The values of partial factors for fatigue reliability design were investigated. It is concluded that fatigue strength standard deviations for twelve kinds of structural details （including influence of stress ratio） in steel crane girders are in the range of 0. 025 1 to 0. 079 2, and the standard deviation of equivalent stress range is 0. 014 8 when its probability distribution follows lognormal distribution. The following design values are suggested： 2.9 for the fatigue reliability index, 1.0 for the partial factor of fatigue strength and 1.14 for the partial factor of fatigue load effect, respectively.

关 键 词：钢吊车梁 高周疲劳 极限状态设计法 可靠指标 分项系数 

分 类 号：TU273.4[建筑科学—建筑设计及理论]