山岭隧道洞身段震害规律与地震风险模糊综合评价分析

A Fuzzy Comprehensive Evaluation of the Seismic Hazard Rule and Relevant Risks for Mountain Tunnel Bodies

隧道洞身段长度因占隧道整个长度的比重较大,发生地震损坏的风险不容忽视。文章通过建立地震风险模糊综合评价模型,对山岭隧道洞身段地震风险进行了分析;收集整理了汶川地震中四川省境内59座山岭隧道震害资料,归纳出了影响隧道洞身段地震反应的10个主要因素,即埋深、施工情况、支护结构及强度、断面大小及形状、地震烈度、地震波传播方向、震中距、隧道长度、断层与软弱破碎带、围岩质量,并总结了与震害的关系;采用层次分析法计算地震风险因素的权重,选取梯形和语意隶属函数,应用模糊数学和加权平均法进行了模糊综合运算。通过将模糊综合评价模型应用于龙洞子隧道的工程实践,得出了洞身段地震风险级别为极高的结论;通过汶川地震中的实际震害也验证了该模型的正确性。

As the tunnel body section is a relatively large proportion of the whole length of a tunnel, seismic risks cannot be ignored. A fuzzy comprehensive evaluation model （FCEM） was established to analyze the seismic risk to the body of a mountain tunnel. Based on data from 59 mountain tunnels damaged by the Wenchuan earthquake in the Sichuan province, 10 influential factors and their relationships to the earthquake were summarized： burieddepth, construction situation, supporting structure and its intensity, section size and shape, seismic intensity, seismic wave direction, epicentral distance, tunnel length, fault and fractured weak zone, and surrounding rock. Furthermore, the analytic hierarchy process was adopted to calculate the weights of influential factors, and a fuzzy calculation was conducted using the trapezoidal and semantic membership function by fuzzy mathematics and weighted average method. FCEM was applied to the Longdongzi tunnel, with the results showing that the seismic risk to the Longdongzi tunnel body is extremely high.