在役钢结构概率安全评定方法

针对大型在役钢结构的安全评定问题,综合利用第二水平法和Monte Carlo法,提出了静载和疲劳条件下概率安全评定的方法;并利用三阶段腐蚀规律对海洋气候腐蚀条件下概率安全评定过程进行了修正.以青岛港装船机主梁和翻车机端环为例进行了实际结构的安全评定分析计算,分别得出了这些结构中一些缺陷的确定性和概率安全评定结果.2种评定结果是大体上是相近的,但也存在一些不同.通过对这些确定性和概率安全评定结果的对比分析,得到了确定性和概率性安全评定方法的初步关系式-近似为单对数线性关系,此结论为概率安全评定方法的工程化奠定了基础.

Investigation of probabilistic safety assessment for in-service mechanical equipment steel structures

To solve the safety assessment problem of large-scale in-service mechanical equipments’ steel structure , the probabilistic safety assessment method was proposed under the dead load and fatigue conditions with the aid of second level method and Monte Carlo method. Amended equation of it was established according to the three-period corrosion law in consider of corrosion lost under marine environment with which the ship loader bridge and wagon tipper in Qingdao Port were calculated and analyzed. Both definite safety assessment and the probabilistic safety assessment results were obtained. The results from the two assessment methods were generally closed but still there was little difference between them. The primary relation-approximately logarithm relationship,between the definite safety assessment and the probabilistic safety assessment was obtained from the comparative investment between the results of two kinds of assessment methods. The relationship obtained is the key point for the effectively application of the concerned probabilistic safety assessment method to in-service mechanical equipments’ steel structure.