结构体系可靠指标及失效概率界限

The Reliability Index of Strueture System and the Limit of Failure Probability

在结构工程的规范中,安全系数设计法正在逐步被更科学的可靠指标设计法所代替.这里的结构可靠指标不同于传统的可靠指标,它是借助于随机变量变异系数和 SN 比的思想建立起来的,并已被国际结构安全委员会(JCSS)所采用.广泛应用于结构工程的可靠设计.本文探讨了抗力和荷载为正态分布、对数正态分布、一般分布等几种情况下,构件及结构体系的可靠指标的确定方法,并应用紧缩法确定了失效概率的界限.

In the structure engineering standards,the more rational and scientific design method of reliability index is gradually replacinq the design method of safe coefficient.The structure reliability index dealt with in this paper is different from the traditional reliability index.It has been established with the aid of the idea about the ratio between the variation coefficient of random variable and SN,and used widely in reliability design of structure engineer- ing.Now it has been accepted by JCSS.In this paper we will discuss the calcu- lating method of reliability index for the member and the structure system in which the resistance and load are in normal dlstribution,logarithmic normal distribution,common distribution,etc.In addition,a limit of failure proba- bility has been set up with the shrinking method.