山岭隧道施工的动态风险管理模型研究

Dynamic rick management model for the construction of mountain tunnel

结合事故树法和专家调查法,确定山岭隧道施工中的风险因素集合与风险评判集合,并引入隶属度矩阵、熵权系数,建立了山岭隧道工程的动态风险管理模型。该模型以定量计算为特征,可实现对顶事件的风险概率计算、面向施工过程中的工况动态风险分析和控制。结合保阜高速公路隧道工程,应用建立的动态风险管理模型,对洞口掘进施工阶段进行了风险分析,并依据得到的风险等级,提出了相应的风险控制措施。

Besides the enhanced construction techniques, dynamic risk management is also critical to prevent unexpected accidents during the construction of mountain tunnel. The potential risk factors of mountain tunnel construction can be expressed with risk management method. The method is able to analyze and control the gusty risk during the construction. Based on fault tree analysis and expertise assessment, the potential risks in every phase of mountain tunnel construction were put forward; the causes and results of potential risks were analyzed. According to the dynamic management flow of mountain tunnel construction, a set of risk factors and risk assessments were obtained. The dynamic risk management model was constructed by introducing theory of membership matrix and entropy coefficient. The model adopted quantitative analysis as characteristics; it was able to execute computation of risk probability of the top events, dynamic risk analysis and operating mode control during the construction process. By referring the construction of Changchengling mountain tunnel for Baofu highway in Hebei province as case study, the proposed dynamic risk management model was applied to analyze the working procedures in the portal excavation stage. Based on the proposed fault tree of mountain tunnel portal excavation stage as well as the design data, field testing data and the expertise analysis result, the grades of risk probability and risk loss were obtained. The corresponding management and control measures for varied risks were brought forth by the risk grade. Due to promptly feedback and accurate reflection on dynamic change of risk, the probability for accident to happen was able to he forecasted and the safety of construction could be better guaranteed.