基于模糊事故树的施工现场地下管线泄漏风险分析

Risk analysis over the underground pipeline leakage in a construction site based on the fuzzy fault tree

针对施工引起的城市地下管线泄漏风险事故频发这一现实问题,考虑施工过程所具有的复杂性和不确定性,提出基于模糊事故树的施工现场地下管线泄漏风险分析方法。对近年城市地下管线泄漏事故资料原因进行统计,根据管线破坏的4种不同情形,从"人-机-料-法-环"着手对"施工现场地下管线泄漏风险事故"进行原因分析并建立事故树。在此基础上结合工程实例引入模糊理论进行定量分析,根据最小割集和结构重要度排序找出该项目引发地下管线泄漏风险事故的主要原因,通过计算顶事件和中间事件发生概率,判断该项目地下管线泄漏风险处于中等风险范围,并提出相应的对策。结果表明,基于模糊事故树的施工现场地下管线泄漏风险分析方法是可行的。

In view of the highly frequent accidents of urban underground pipeline leakage due to the complexity and uncertainty in the construction process,a risk analysis of the underground pipeline leakage in engineering construction is proposed based on fuzzy fault tree in this paper. In doing so,four different ways of pipeline damage is classified through the statistical analysis of the likely causes of such leakage accidents in recent years at first. Then the cause analysis of the top event‘underground pipeline leakage accident in construction＇is carried out based on the‘human-machine-material-method-environment＇system,as the fault tree is established. Furthermore,the fuzzy method is introduced to conduct the quantitative analysis by taking ‘Line 4 of Changsha Subway＇as an application case. The minimal cut sets and the coefficients for the structure importance intend to show the principal causes leading to the pipeline leakage,particularly,during the period of construction,when such accidents take placemore often due to ‘the shortage of dynamic information feedback of regular deformation inspection of the pipelines and the surrounding soil ＇. ‘The ineffective inspection and supervision on the site＇,‘failure to establish an emergency rescue mechanism＇in addition to ‘the lack of efficient protection of the pipelines,such as the soil reinforcement or isolation etc. ＇should be responsible for such events. The calculation and the evaluation results of the leakage accidents indicate that the risk situation faced by the underground pipeline leakage of the said construction project can be attributed to the medium level,which is in accord with the actual situation of the project. To answer to the need for improvement, the following corresponding countermeasures have been proposed based on the above analysis. The results show that the fuzzy fault tree method turns to be suitable and applicable to the purpose. And,the study can help to lay a scientific basis for the safety management of such construction companies and enterprises in safety protection of urban underground pipeline systems.