城市地铁交通雷击风险评估与模拟仿真研究

雷电灾害是城市地铁交通安全运行的潜在危险因素,因此对地铁进行科学规范的雷击风险评估并采取针对性的防雷技术措施就显得非常重要。借鉴自然灾害风险区划的理论及方法,提出了城市地铁交通沿线区段、地面建筑单体雷击风险评估的方法,建立了地面高架站接触网架空地线雷击感应过电压仿真模型。以呼和浩特地铁交通项目为实例,给出了地铁沿线区段雷击区域评估指标,通过对地铁沿线的地闪定位、雷电灾害、土壤电阻率及周边环境等数据资料的分析计算得出区域风险评估结果;并对雷击极高风险区段的地面建筑物单体进行了评估,结果表明入户管线附近落雷是建筑物单体总雷击次数的主要因素;进而对雷击附近大地在高架站接触网架空地线产生的感应过电压进行了模拟计算,给出了雷击点距架空地线的距离、高架桥高度以及架空地线支柱接地电阻和间距等因素对感应过电压的影响规律。城市地铁交通全线段及差异化防雷评估技术手段,为城市地铁交通防雷设计和安全运行提供更加客观准确的科学依据。

Study on Lightning Hazard Risk Evaluation and Simulation ofUrban Subway Traffic

Lightning disaster is a potential risk factor for the safe operation of urban subway traffic. Therefore, it is very important to carry out scientifically standardized lightning risk evaluation and take targeted lightning protection measures. We have put forward the method of lightning risk evaluation of the section along urban subway and the single ground building based on the theory and method of natural disaster risk zoning, and a simulation model of lightning induced overvoltage of overhead ground line is established. Through the example of Hohhot subway traffic project, the evaluation index of lightning strike area along the subway line is given, and the calculation method and process of casualty loss and economic loss risk in different sections are put forward. Through the analysis of the lightning location, lightning disaster, soil resistivity and surrounding environment along the subway, the results of regional risk assessment are calculated.And the single building in the extremely high risk zone of the lightning strike were evaluated, the results show that the lightning strike near the entrance line was the main factor for the total number of lightning strikes in the building, the overhead line induced overvoltage of subway elevated station catenary by lightning strikes the ground were calculated. The influence of the lightning distance from the overhead ground line, the height of the viaduct and the grounding resistance and spacing of the overhead ground strut were given. In this paper, the whole line segment and differential lightning protection evaluation methods of urban subway traffic are put forward, which provide more objective and accurate scientific basis for the lightning protection design and safe operation of urban subway traffic.