基于改进的G2-AEW-UMT模型的水工隧洞施工安全风险评价及障碍因子诊断

Safety risk evaluation and diagnosis of hydraulic tunnel construction based on G2-AEW-UMT Model

为降低滇中引水工程隧洞施工安全风险,预防安全事故的发生,对风险因子须提前预判。考虑隧洞施工孕险环境和水文、气象、工程地质等因素,结合规范和工程实际,遴选出8个一级指标和19个二级指标构建水工隧洞施工安全风险评价指标体系。采用改进G2、反熵权法(AEW)计算指标主客观权重,通过未确知测度理论(UMT)并引入障碍因子诊断,建立改进的G2-AEW-UMT水工隧洞施工安全风险评价模型。以某工程7^(#)隧洞为例进行模型验证,结果表明:隧洞斜井段、进口段和出口段障碍度最高的是气候条件,障碍度分别为27.79%,32.97%,29.75%;上游段主要障碍因子为地质条件,障碍度为28.93%;下游段主要障碍因子为水文条件,障碍度为22.96%;综合诊断表明影响7^(#)隧洞施工安全的主要障碍因子为气候、水文和环境条件,其障碍度均值之和达到49.55%,风险范围程度为62.5%,综合评价该水工隧洞施工安全风险等级为Ⅱ级,属于中风险,对比模糊综合评价结果与前人的研究,该模型评价结果符合工程实际,验证了模型的可行性。将未确知测度理论结合障碍因子诊断模型应用于水工隧洞施工安全风险评价的适用性好、计算精度高,可为滇中引水工程水工隧洞施工安全风险评价与诊断提供新思路。

In order to reduce the construction safety risk of tunnels in Yunnan Central Water Diversion Project and prevent the occurrence of construction accidents,it is necessary to predict the risk factors in advance.Considering the construction risk-inducing environment and hydrological,climatic and geological factors,we selected 8 primary indices and 19 secondary indices to build a safety risk evaluation index system for the construction of hydraulic tunnels,taking the specifications and engineering practice into account.The improved G2 and anti-entropy weight(AEW)method were introduced to calculate the subjective and objective weights of the indices,then the uncertainty measurement theory(UMT)and obstacle factor diagnosis were applied to establish the G2-AEW-UMT hydraulic tunnel construction safety risk evaluation model.The model validation was carried out on the simulation of the No.7 tunnel of a project,and the results showed that the obstacle degree of climatic conditions in the slanting section,inlet section and outlet section of the tunnel scores the highest,which are 27.79%,32.97%and 29.75%,respectively;that of geological conditions in the upstream section is the highest,which is 28.93%;and that of hydrological conditions in the downstream section scores the highest,which is 22.96%.According to the comprehensive diagnosis,the main obstacle factors affecting the construction safety of No.7 tunnel are climatic,hydrological and geological conditions,the mean value of the obstacle degree is 49.55%and the risk range degree is 62.5%,so the construction safety risk level of this hydraulic tunnel is evaluated asⅡ,which is categorized as the medium risk.Compared with the previous research,the fuzzy comprehensive evaluation results are consistent with the engineering practice,therefore,the proposed model is feasible.The combined model of unconfirmed measurement theory and obstacle factor diagnosis is applicable to the hydraulic tunnel construction safety risk evaluation with high feasibility and calculation accuracy,which can provide a new approach for the safety risk evaluation and diagnosis of the hydraulic tunnel construction in the Yunnan Central Water Diversion Project.