城镇燃气管道动火作业安全评价

针对城镇燃气管道动火作业的高危险性，为保障生命财产安全，提出一种基于未确知测度的安全评价方法。首先，从动火施工作业的前、中、后3个阶段对整个作业过程进行安全分析，并基于作业的前阶段建立安全评价体系。然后，引入未确知测度模型，将因素的量化值与测度函数结合得出测度评价矩阵，采用变异系数法处理评价矩阵，确定各危害因素的客观权重。最后，根据测度评价矩阵与因素权重得出动火作业的安全等级，并对危害因素进行排序。实例结果表明:应用该方法能有效地确定出城镇燃气管道动火作业的安全等级，对于不安全的施工作业，可根据排序确定高危险因素，并采取措施降低其危险性，提高整个动火作业过程的安全性。

Research on risk assessment method of third-party construction damage for urban gas pipeline

A semi-quantitative risk assessment method for urban gas pipeline was proposed in order to reduce the adverse effect of third-party construction damage. Firstly, the failure factors were determined based on the system of "man-machine-environment-management", the factor weights were determined by G2 weighting method, and the matter element model was introduced to analyze the failure probability. Secondly, the mathematical models of jet flame, flash fire and vapor cloud explosion were established to calculate the damage area and determine the grade of failure consequence. Finally, the risk level of third-party construction damage for urban gas pipeline was obtained according to the risk matrix in API 581. Example analysis showed that this method combines the advantages of qualitative evaluation and quantitative evaluation. It can analyze the risk more accurately and effectively to determine the risk level.