钢吊车梁疲劳设计可靠指标及分项系数研究.

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 0.0792, and the standard deviation of equivalent stress range is 0.0148 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. [ABSTRACT FROM AUTHOR]