基于物元和可拓集合理论的燃气管道风险等级评定

对城市燃气管道进行风险评估和风险等级划分，进而实现风险管理，是保证燃气管道安全运行、提高管道公司经济效益的科学管理方法。风险等级的划分需要兼顾影响管道失效可能性的各个因素以及燃气管道可能造成的失效后果，目前常用的分级方法，如等分法、正态分布3 σ法等虽可解决一定问题，但比较粗糙且缺乏理论依据。在对城市燃气管道风险等级进行初步定义的基础上，引入物元和可拓集合相关理论对燃气管道风险构成因素进行分析研究，使用关联函数和同征物元体等工具函数对燃气管道风险等级进行定义和计算，确定了计算函数和计算过程；应用一个实例简要介绍了燃气管道风险等级划分的主要计算过程和方法；并对城市燃气管道风险等级评定提出了相应的处理措施。

Risk grade evaluation of gas pipelines based on matter-element and extension set theories

To perform risk evaluation and risk grade division on gas pipelines for risk management is a scientific management method to ensure safety operation and to boost the benefit of pipeline companies. Various factors which affect pipeline failure probability and probable results caused by gas pipeline failure should be taken into consideration in risk grade division. Although the commonly used risk grade division methods, including equal division method and three σ method, can solve some problems, they are still unshaped and lack of theoretical basis. Based on preliminary definition of urban gas pipeline risk grade, relevant theories about matter element and extension set are introduced to analyze constitutive factors for gas pipeline risk. Some tool functions, like correlation function are used to define and calculate the risk grade of gas pipeline; calculation functions and procedures are identified. Besides, a practical example is proposed. The main calculation methods for risk grade division are introduced according to its calculation process. Corresponding measures are put forward for risk grade evaluation of urban gas pipeline.