构件可靠度与平均安全系数的研究

构件可靠度的研究是结构可靠性分析的基础,其正确的计算方法对结构的安全可靠性评定具有重要意义.以应力-强度干涉模型为基础,探讨了当构件的应力和强度按不同分布时,构件可靠度和平均安全系数的计算方法以及二者之间的关系.计算表明:当构件的应力和强度按正态分布或其它分布处理时,对构件平均安全系数的影响很小,而对构件可靠度有较大的影响.对一般构件来讲,应力和强度采用正态分布是合理的,且偏于安全;对可靠度要求很高的构件来讲,建议采用对数正态分布或威布尔分布.

Study on Reliability and Mean Safety Coefficient of Components

Based on stress strength interference model, calculation formula of reliability and mean safety coefficients and their relationships are derived, corresponding to different distributions of stress and strength. Through practical calculations it is shown that, when the distributions of stress and strength are subordinated to normal distribution or others, the value of mean safety coefficients is about the same, though the value of reliability is quite different. It is safer for common components to use normal distribution, and it is more exact for very important components to use logarithmic normal distribution or Weibull distribution.