基于围岩监测的隧道施工期突涌水风险预测

Assessment of water inrush risk during tunnel construction based onsurrounding rock monitoring

突涌水灾害的频发对隧道安全施工和生命财产构成严重威胁,因此精准预测并有效控制隧道施工中的突涌水风险尤为重要。本研究旨在提出一种适用于隧道施工期的突涌水风险预测方法,通过反馈施工现场监测数据确定风险概率并预测水量范围。首先,在分析施工期突涌水事故案例的基础上,综合考虑地质构造和水文地质条件,并引入开挖支护、动态监测围岩以及渗压信息,建立了包含10个指标在内的突涌水评估指标体系;其次,采用博弈论组合赋权法优化主客观权重向量,构建改进功效系数模型以计算各风险等级下的综合功效系数,并在归一化处理后确定风险发生概率;最后,根据最大隶属度原则确定风险等级并预测水量范围。以鸡公岭隧道和跃龙门隧道为例,应用该方法对施工中的突涌水风险进行了预测。结果表明:所提出的基于博弈论组合权重和改进功效系数的隧道施工期突涌水灾害风险预测方法与现场开挖结果吻合较好;该方法综合考虑评估指标和风险等级之间非线性关系使预测结果更接近实际施工情况,在评估风险等级的同时实现了风险概率和涌水量范围的预测。

The frequent occurrence of water inrush disasters poses a significant threat to tunnel construction safety,as well as human lives and properties.Therefore,it is crucial to accurately predict and effectively control the water inrush risk during tunnel construction.This study aims to propose a tunnel construction period-specific method for predicting water inrush risk,determining the probability of risk,and indicating the range of water quantity by incorporating construction site monitoring data.First,comprehensive consideration is given to the geological structure,and hydrogeological conditions based on analyzing water burst accident cases during construction.Information regarding excavation and support,dynamic monitoring of surrounding rock,and osmotic pressure is incorporated to establish an evaluation index system for water inrush consisting of 10 indicators.Then,the game theory method is employed to optimize the combination weighting.Additionally,an improved efficiency coefficient model is constructed for calculating the comprehensive efficiency coefficient at each risk level,followed by determining the normalized probability of risk occurrence.Finally,based on the principle of maximum membership degree,the risk level and the water inrush scope are determined.Taking Jigongling Tunnel and Yuelongmen Tunnel as cases,this approach forecasts the risk during construction.The results show that the proposed method,which integrates the game theory,combined weight,and an improved efficiency coefficient,aligns well with the actual excavation outcomes at the site.It comprehensively considers the non-linear relationship between evaluation indices and risk grades,resulting in a prediction outcome that closely reflects the actual construction conditions.Furthermore,it enables the estimation of both risk probability and water inrush range while evaluating risk grades,thereby offering a novel approach for accurately assessing water inrush risks during tunnel construction.