基于宏观地质模型分类的深埋输水隧洞衬砌外水压力研究  

Study on External Water Pressure in Deep Buried Water Conveyance Tunnel Lining based on Macroscopic Geological Model Classification

作　　者：雒少江 丁卫华[1] 薛海斌 李玉波[2] 严广艺[2] 宋常贵 张东旭 LUO Shao-jiang;DING Wei-hua;XUE Hai-bin;LI Yu-bo;YAN Guang-yi;SONG Chang-gui;ZHANG Dong-xu(School of Civil Engineering and Architecture,Xi′an University of Technology,Xi′an 710048,Shaanxi Province,China;China railway first survey and design institute group CO.,LTD.,Xi′an 710043,Shaanxi Province,China)

机构地区：[1]西安理工大学土木建筑工程学院,陕西西安710048 [2]中铁第一勘察设计院集团有限公司,陕西西安710043

出　　处：《中国农村水利水电》2024年第12期177-184,192,共9页China Rural Water and Hydropower

基　　金：国家自然科学基金(52009107,52078421);联合基金项目-企业-引汉济渭(2021JLM-50);引汉建函(2014)93号-07-01;中铁一院SPS-D-04-地-3。

摘　　要：衬砌的外水压力对富水深埋隧洞衬砌厚度和排水方案的确定具有重要意义。现有研究往往忽略宏观地质条件对渗流场的影响规律分析,导致深埋隧洞外水压力估算结果和衬砌设计方案缺乏可靠性的评价。论文依托引汉济渭秦岭输水隧洞工程,将富水地区深埋隧洞概化为分水岭下、傍山区域、河流下3种代表性的宏观地质环境模型,研究地质条件因素和工程措施对围岩渗流场和衬砌外水压力的影响规律和机理。结果表明:①洞顶地下水高度相同和衬砌不透水条件下,分水岭隧洞周围地下水的渗流方向以竖向为主;河流下隧洞周围地下水的渗流方向以水平为主。分水岭隧洞、傍山区域隧洞、河流下隧洞外水压力折减系数依次增大。分水岭下隧洞外水压力折减系数随着埋深增大而增大,依次为0.72、0.77、0.84;而傍山隧洞、河流下隧洞外水压力折减系数几乎不变,分别是0.91、0.91、0.93和0.95、0.96、0.96。②采取相同排水措施后,随着埋深增大,分水岭隧洞外水压力折减系数依次为0.15、0.42、0.64,降压效果最好;而傍山隧洞、河流下隧洞外水压力折减系数分别是0.48、0.67、0.77和0.63、0.80、0.83,降压效果逐渐变差;③隧洞埋深1200 m时,分水岭、傍山和河流下隧洞外水压力折减系数随着围岩渗透系数的增大外水压力折减系数分别介于0.43~0.73、0.67~0.89和0.80~0.95,均呈现外水压力随着隧洞埋深增大而增大的规律性。研究成果具有普适性,可以从隧洞宏观水文地质条件与外水压力折减系数的规律性评估富水地区隧洞衬砌抗水压设计的合理性。The external water pressure of lining is of great significance to the determination of lining thickness and drainage scheme of waterrich deep buried tunnel.The existing research often ignores the analysis of the influence of macroscopic geological conditions on the seepage field,which leads to the lack of reliability evaluation of the external water pressure estimation results and lining design schemes of deep bur⁃ied tunnels.Based on the Qinling Water Conveyance Tunnel Project of Hanjiang-to-Weihe River Diversion Project,this paper generalizes the deep-buried tunnel in the water-rich area into three representative macro-geological environment models under the watershed,the mountainside area and the river,and studies the influence law and mechanism of geological conditions and engineering measures on the seep⁃age field of surrounding rock and the external water pressure of lining.The results show that:①The seepage direction of groundwater around the watershed tunnel is mainly vertical under the condition of the same height of groundwater at the top of the tunnel and impermeable lining.The seepage direction of groundwater around the tunnel under the river is mainly horizontal.The external water pressure reduction coefficient of the watershed tunnel,the tunnel near the mountain area and the tunnel under the river increases in turn.The reduction coefficient of exter⁃nal water pressure of tunnel under watershed increases with the increase of buried depth,which is 0.72,0.77 and 0.84 respectively.The re⁃duction coefficients of the external water pressure of the mountain tunnel and the river tunnel are almost unchanged,which are 0.91,0.91,0.93 and 0.95,0.96,0.96,respectively.②After the same drainage measures are taken,with the increase of buried depth,the reduction co⁃efficients of external water pressure of watershed tunnel are 0.15,0.42,0.64 respectively,and the pressure reduction effect is the best.The external water pressure reduction coefficients of the tunnel near the mountain and the tunnel under th

关 键 词：富水深埋隧洞 宏观地质模型 衬砌 外水压力 排水孔 

分 类 号：TV672.1[水利工程—水利水电工程]