西南山区某深埋长大隧道水文地质特征及突涌水危险性分析  

Analysis of Hydrogeological Characteristics and Water Burst Risk of a Deep and Long Tunnel in Southwest Mountainous Area

作　　者：索朗[1] 徐正宣[1] 宋章[1] 周航 SUO Lang;XU Zhengxuan;SONG Zhang;ZHOU Hang(China Railway Eryuan Engineering Group Co.,Ltd.,Chengdu 610031,China)

机构地区：[1]中铁二院工程集团有限责任公司,成都610031

出　　处：《高速铁路技术》2023年第3期97-101,共5页High Speed Railway Technology

摘　　要：西南山区某隧道处于龙门山断裂带西南段内,区域地质构造作用强烈,地形地貌及岩溶水文地质条件复杂,突涌水成为制约隧道勘察设计和安全施工的重大难题。本文采用现场水文地质调查、水化学成分测试、理论分析计算等方法分析了隧道的岩溶发育程度和岩溶发育规律;依据岩溶水补径排条件,划分了工程区水文地质单元;在水文地质分区的基础上,进行了隧道涌水量预测和隧道涌突水危险性评价。研究结果表明:(1)该隧道二叠系栖霞组(P_(1)q)、奥陶系中统宝塔组(O_(2)b)为强富水性,泥盆系养马坝组(D_(2)y)、泥盆系中统观雾山组(D_(2)g)、志留系下统纱帽组(S_(2)s)、志留系下统罗惹坪组(S_(2)l)为中等富水性,晋宁澄江期斜长花岗岩(γ_(2))、震旦系下统安山岩段(Zaα)以及志留系,泥盆系地层中的砂岩和泥岩为弱富水性;(2)该隧道高危险突涌水段650 m,占比4.42%;中危险突涌水段5879 m,占比39.98%;较危险突涌水段7742 m,占比52.64%;低危险突涌水段435 m,占比2.96%。本文研究成果对西南山区铁路岩溶区高压富水隧道勘察设计和施工具有重要参考价值。A tunnel in the southwest mountainous area is located in the southwest section of the Longmenshan fault zone,its regional geological structure is strong,and the topography and karst hydrogeological conditions are complex.Water burst is thus a major problem restricting the survey,design and safe construction of tunnels.The karst development degree and law of the tunnel were analyzed by means of on-site hydrogeological survey,hydrochemical composition test,theoretical analysis and calculation.The hydrogeological units in the project area were divided according to the karst water recharge,runoff and drainage conditions,and on the basis of hydrogeological division,the tunnel water inflow was predicted and its inrush risk was assessed.The results of the study show that:(1)The Permian Qixia Formation(P1q)and Middle Ordovician Baota Formation(O_(2)b)are strongly water-rich,the DevonianYangmaba Formation(D_(2)y),Middle Devonian Guanwushan Formation(D_(2)g),Lower Silurian Shamao Formation(S_(2)s),and Lower Silurian Luoreping Formation (S_(2)l)are moderately water-rich,and the plagiogranite (γ_(2))of Jinning-Chengjiang period,Lower Sinian Andesite section (Zaα),and the sandstone and mudstone in the Silurian and Devonian strata weakly water-rich.(2) The tunnel section at high risk of water burst is 650 m long,accounting for 4.4_(2)% of the total length;the section at medium risk of water burst is 5 879 m long,accounting for 39.98%;the section at risk of water burst is 7 742 m long,accounting for 52.64%;the section at low risk of water burst is 435 m long,accounting for2.96%.The findings of this paper provide an important reference for the survey,design and construction of railway tunnels in high-pressure and water-rich karst areas in Sichuan’s southwestern mountainous regions.

关 键 词：西南山区 深埋长大隧道 水文地质特征 突涌水 危险性分析 

分 类 号：U452.11[建筑科学—桥梁与隧道工程]