高家坪隧道地下水系统识别及涌水量预测

Systematic Identification of Groundwater and Prediction of Water Inflow of Gaojiaping Tunnel

以宜保高速高家坪隧道为研究对象,重点剖析高家坪隧道工程区的地质条件,在此基础上,综合采用地下水示踪试验、地下水化学组分测试、降雨量与地下水动态长期观测等多种技术手段对高家坪隧道区域岩溶发育特征、岩溶隧道突涌水条件进行了分析和探索,查明了各岩溶水系统的边界及之间的水力联系,分析了岩溶系统与隧道的空间关系及其对隧道安全的影响,揭示了岩溶系统的水文响应特征,并采用分布式TOPMODEL流域水文模型模拟流域的流量过程,预测了隧道的正常和最大涌水量。结果表明:隧道ZK45+500~ZK46+900段涌水最大峰值流量可达3.56 m3/s,滞后降雨3 h,最大涌水量47 984.7 m3/d,与实测值吻合较好。本文工作可为我国岩溶地区类似隧道工程的突涌水灾害预防提供参考和指导。

Taking the Gaojiaping tunnel of Yicheng-Baokang highway as an example,this paper comprehensively analyzes the geological condition of tunnel region. Based on this,by applying the integrate techniques including groundwater tracer test,chemical identification and dynamic observation of rainfall and groundwater,the karst developing characteristics and tunnel gush condition are researched. The boundaries of karst water subsystems and their hydraulic connections are investigated,and the spatial relationship of karst system and tunnel and its influence on the safety of tunnel are analyzed. The hydrologic response feature of karst system is revealed,and by using distributed TOPMODEL basin hydrologic model,the normal and maximal water inflow of tunnel is predicted. The results show that the maximal peak flux at ZK45 ＋ 500 ~ ZK46 ＋ 900 of tunnel is 3.56 m3/s,and the maximal water inflow appeared 3 h later than the rainfall reaches 47 984.7 m3/d,which agrees well with the measured value. This work can provide the reference and guidance for the prevention and control of water gush in similar tunnel engineering in karst area of China.