摘要
在既有结构的可靠性评定中,对作用、抗力变异系数的推断将成为一项必要的工作。目前已有的变异系数推断方法主要适用于对永久作用、材料强度等正态随机变量变异系数的推断,但其中的精确方法需采用查表计算,应用不便,而近似推断方法中又设定了较为严格的适用条件。通过变换变异系数的概率表达式和引入相关的近似分布,提出了永久作用、材料强度变异系数的近似推断方法。对比分析结果表明:该方法不仅应用简便,而且较目前的近似方法,包括GB/T 11791—89中的近似推断方法具有更高的精度,适用范围更广。同时针对服从对数正态分布的抗力,提出了变异系数推断方法,包括直接和间接两种推断方式,能够满足工程实际的需要。
In the reliability assessment of existing structures, statistical inference for coefficient of variation of action and resistance is an essential task. The present inference method for coefficient of variations is mainly applicable to normal random variables which are adopted to infer the coefficient of variation of permanent action and material strength, but the application of its precise method of calculation is inconvenient, while the approximate inference method can only be used with stringent conditions. This paper proposes an approximate inference method for coefficient of variation of permanent action and material strength by changing coefficient of variation related to the probability expression and by leading into approximate distribution. Comparative analysis of results shows that the proposed method is not only simple and convenient to use, but is also more accurate compared with the approximate inference method specified in the national standard GB/T 11791--89 and can be suitable for a wider range of application. In addition, the paper proposes inference method for coefficient of variation of structure resistance that obeys the lognormal distribution. The approach can satisfy the needs of practical design,with the consideration of the direct and indirect inference methods.
出处
《建筑结构学报》
EI
CAS
CSCD
北大核心
2010年第8期101-105,共5页
Journal of Building Structures
基金
国家自然科学基金项目(50678143)
关键词
既有结构
作用
抗力
统计推断
可靠性评定
existing structure
action
resistance
statistical inference
reliability assessment
