含缺陷压力容器的概率失效分析研究进展

Review on failure analysis of pressure vessels containing defects based on probabilistic fracture mechanics

不确定性因素的统计模型和失效概率的计算方法是解决含缺陷压力容器概率断裂力学分析的重要环节。本文对以概率断裂力学理论为基础的各种不同工况下含缺陷压力容器失效分析和安全可靠性评定的研究现状进行了综述,总结了材料强度、断裂韧性、温度、缺陷尺寸及检出率等不确定性因素的常用分布特征,归纳了常用压力容器失效概率的计算方法,并进一步分析了失效概率的三种计算方法——直接解析积分法、近似法和数值模拟法的特征。本文不但提供了解决该领域内工程问题最新的方法,而且指出了目前面临的理论挑战。

The statistical model and the evaluation method of the failure probability play a key role in the probability fracture mechanics analysis of pressure vessels containing defects.In this paper,a survey is conducted on the recent progress of the failure analysis and safety reliability assessment of pressure vessels containing defects under different conditions in terms of the probabilistic fracture mechanics.With the review of statistical characteristics of material strength,toughness,temperatures,defect scales,detection rate,and other uncertainty factors,the frequently used evaluation methods of failure probability for pressure vessels are surveyed.Furthermore,three evaluation methods,namely,directly analytic integral method,approximate method and numerical simulation method,are analyzed in details.It not only provides some feasible methods for handling practical engineering problems,but also proposes some challenging theoretical problems in this field.