引汉济渭工程黄三隧洞地下水渗流同位素综合示踪探测分析研究

引汉济渭工程黄三段深埋长输水隧洞岩性复杂多变,水文地质条件极其复杂。为深入分析黄三段水文地质条件,采用地下水同位素综合示踪探测手段,对黄三隧洞沿线钻孔、大坪隧道、良心河、沙坪河等区域进行现场测试及取样室内分析。通过对温度、电导、水化学及环境同位素、地下水流速等方面的综合分析,结合水文地质测绘、试验等基础性工作,对地下水补给、径流、排泄条件,水力联系及连通性等方面进行了评价。研究结果表明:黄三隧洞南部和中部存在富水带,地下水主要受大气降水补给;围岩可划分为中等富水区、弱富水区、贫水区,分别占隧洞全长的7.9%、15.4%、76.7%;实际揭露涌水量与原设计预测情况一致,验证了同位素综合示踪探测方法的有效性。研究成果对同类工程具有一定的工程实际应用参考价值。

Analysis on comprehensive isotopic-tracing detection of underground water seepage in Huangsan Tunnel of Hanjiang River to Weihe River Valley Water Diversion Project

The lithology of the deeply buried water conveyance tunnel of Huansan Section for Hanjiang River to Weihe River Water Transfer Project is complicated and variable under a quite complicated hydrogeological condition. In order to deeply analyze the hydrogeological condition of Huangsan Section， the method of comprehensive underground isotopic-tracing detection is adopted for the in situ testing and the indoor sampling analysis made on the areas of the drillings along the line of Huangsan Tunnel， Daping Tunnel， Liangxinhe Rover， Shapinghe River， etc. Through the comprehensive analysis made in the aspects of temperature， conductance， water chemistry， environment isotope， groundwater flow rate， etc.， the conditions of groundwater recharge， runoff， discharge， etc. and the hydraulic connection as well as the connectivity therein are evaluated in combination with the basic works of hydrogeological survey and experiment concerned. The result show that there are water-rich areas surrounding southern and central Huangsan Tunnel，in which groundwater is mainly affected by the meteoric water; the surrounding rock can be divided into secondary water-rich area，weak water-rich area and water-poor area，accounted for 7.9%，15.4% and 76.7% in the tunnel.The actually exposed water burst amount is coincided with that from the prediction made in the original design， and then the availability of the method of the comprehensive isotopic-tracing detection is verified as well. The result obtained herein has a certain reference value for the similar project.