可拓理论在天然气管道失效可能性评价中的应用

Application of extension theory on failure possibility evaluation of natural gas pipelines

为了准确地判定天然气管道失效可能性,应用可拓理论,建立基于物元和关联函数的失效可能性等级评价流程。基于物元理论,将管道失效等级、评价指标、指标值域结合为一体,构建评价指标体系和评价标准,并对定性指标进行量化,对各指标进行归一化处理,确定经典域和节域;利用可拓集合的关联函数计算评价指标对失效可能性等级的关联系数,并引入3标度层次分析法(AHP)计算指标权重;根据级别变量特征值判定管道失效可能性等级,建立基于改进AHP法的可拓评价方法;将该方法应用于国内某4个典型天然气管段的失效可能性等级评价。研究结果表明:该方法能够准确地反映天然气管道失效可能性等级偏向另一级的程度,具有较好地适用性。

In order to accurately determine failure possibility of nature gas pipelines,an evaluation procedure was established by using of the extension theory. The procedure is based on the matter-element theory and dependent function and consists of following steps. Firstly,based on matter-element theory,pipeline failure possibility,evaluation indexes and indexes＇ value range were combined together. An evaluation index system and classification standards were established. Qualitative indexes were quantified,evaluation indexes were normalized,classical domain and joint domain were set up as well. Secondly,comprehensive correlative degrees of evaluation indexes were calculated using dependent function of extension set,of which the weight coefficients were determined by 3 scale AHP. Then,eigenvalues of grade variables were used to determine the failure rank of natural gas pipelines,and an improved AHP based on extension evaluation method was established. Finally,the method was used to evaluate failure possibility levels of 4 typical natural gas pipeline sections in China. The results show that this method can precisely reflect failure possibility levels of pipelines.