摘要
某国家重大引调水工程引水隧洞将穿越聚龙山向斜可溶岩地层,可能面临严重岩溶涌突水问题。为了查明隧洞突涌水条件,选择岩溶水害风险较低的引水方案,综合采用岩溶水文地质调查、水化学与同位素分析等方法对聚龙山向斜岩溶水流系统特征进行了识别。结果表明:聚龙山向斜含水系统具有"两含夹一隔"的多层结构,下部二叠系主要为埋藏型岩溶弱发育区,而上部三叠系裸露型岩溶区中发育了具有多级水流系统的巨型岩溶汇水盆地。穿聚龙山向斜段工程论证的3个方案中,A线方案从向斜西段岩溶水系统的补给区穿越,隧洞穿可溶岩段长度短、且全部为埋藏型岩溶,剖面上绕避了三叠系岩溶汇水盆地,发生岩溶涌突水的风险低;而B线方案和C线方案均进入了三叠系岩溶汇水盆地,穿越裸露型可溶岩段的长度大,遭遇高压岩溶突水的风险高,故推荐A线引水方案。研究成果可为引水隧洞线路比选提供科学依据,对类似深埋长隧洞工程建设也具有参考价值。
A critical water diversion project may face serious water inrush problems during tunnel construction when it crosses the carbonate rock formations of Julongshan syncline.Characteristics of karst water flow system in Julongshan syncline were identified by multi-methods such as karst hydrogeological field survey, hydrochemistry and isotope analysis, to find out the hydrogeological conditions of water inrush into the tunnel and select one water diversion scheme with lower risk of karst water disaster.The results show that the aquifer system in Julongshan syncline has a multi-layer structure with an impermeable layer between two aquifers.The Lower Permian is mainly buried underground with weak karst development, while the Upper Triassic bare karst area forms a giant karst basin with multi-stage water flow system.Three tunnel plans were demonstrated in Julongshan syncline area.Plan A passes through the recharge area of the karst water system in the western syncline, in which the length of soluble rock the tunnel passes through is the lowest and all belong to buried karst.It avoids to cross the Triassic karst water basin in the profile, therefore the risk of water-gushing for Plan A is relatively low.However, Plan B and Plan C will cross the Triassic karst water basin with longer soluble rock section and the risk of suffering karst water-gushing is much higher.So, Plan A is recommended.This study can provide a scientific basis for comparison and selection of diversion tunnel line, and also has reference value for similar deep-buried long tunnel construction.
作者
颜慧明
常威
郭绪磊
邓争荣
黄琨
Yan Huiming;Chang Wei;Guo Xulei;Deng Zhengrong;Huang Kun(Changjiang Geotechnical Engineering Co.Ltd.,Wuhan 430010,China;School of Environmental Studies,China University of Geosciences(Wuhan),Wuhan 430078,China)
出处
《地质科技通报》
CAS
CSCD
北大核心
2022年第1期127-136,共10页
Bulletin of Geological Science and Technology
基金
国家自然科学基金项目(42172281)。
关键词
深埋长隧洞
岩溶
涌突水条件
多级水流系统
线路比选
deep-buried long tunnel
karst
water-gushing conditions
multi-stage water system
line comparison
