含腐蚀缺陷悬空管道的考虑多个变量相关性的非概率时变可靠性分析

Non-probabilistic and Time-varying Reliability Analysis of Suspended Pipeline with Corrosion Defects Considering the Correlation of Multiple Variables

考虑管道工程中的小样本数据难以得到准确的概率分布且采集数据需大量费用,且影响不确定因素相互影响的前提下,在研究其可靠性时提出利用非概率集合理论凸方法为理论基础的椭球模型。考虑结构抗力随时间衰变的客观特性,基于随机过程的时变可靠性分析需要大量的数据,提出了更符合实际情况的随时间抗力的时间累计效应产生的衰变和腐蚀随时间增长向相结合的模型,并结合实际带腐蚀缺陷的悬空管道的极限悬空长度式子,建立了考虑腐蚀缺陷悬空管道的时变极限状态方程,进行二维与三维的不确定变量相关性的非概率可靠性分析。可以作为基于随机过程理论的腐蚀悬空管道的时变可靠性分析理论的有效补充,为埋地油气管道的维护提供理论依据。

Considering that small sample data in pipeline engineering, it is difficult to obtain accurate probability distribution and collect data which requires a large amount of cost. In addition, affecting the mutual influence of uncertain factors, it is proposed to use non-probability set theory convex method as the theoretical basis when studying its reliability. Considering the objective characteristics of structural resistance decay with time and the time-varying reliability analysis based on random process requires a large amount of data, the decay and corrosion of time-dependent growth due to the effect of time are proposed. Combined with the model, the ultimate suspended length formula of the suspended pipeline with corrosion defects, the time-varying limit state equation considering the corrosion-defective suspended pipeline is established. And the non-probabilistic time-varying reliability is analyzed. It can be used as the corrosion vacancy based on random process theory. Above all, it provides a theoretical basis for the maintenance of buried oil and gas pipelines.