基于数字图像修正HC法的水工隧洞围岩精细化分级研究  

Research on Fine Classification of Surrounding Rock in Hydraulic Tunnels Based on Digital Image Correction HC Method

作　　者：李颂章 李星霖 韦凡秋 罗亮明 夏裕栋 LI Song-zhang;LI Xing-lin;WEI Fan-qiu;LUO Liang-ming;XIA Yu-dong(Hunan Provincial Water Resources and Hydropower Survey,Design,Planning and Research Institute Co.,Ltd.,Changsha 410000,Hunan Province,China;Central South University of Forestry and Technology,Changsha 410000,Hunan Province,China;Central South University,Changsha 410000,Hunan Province,China)

机构地区：[1]湖南省水利水电勘测设计规划研究总院有限公司,湖南长沙410000 [2]中南林业科技大学,湖南长沙410000 [3]中南大学,湖南长沙410000

出　　处：《中国农村水利水电》2024年第11期227-232,246,共7页China Rural Water and Hydropower

基　　金：国家自然科学基金项目(52378426、52378422);犬木塘水库工程科技创新项目(W-2022-72)。

摘　　要：现有水工隧洞围岩分级方法仍以经验性为主,易造成围岩分级结果存在偏差,进而导致隧洞支护设计不合理,甚至开挖过程发生围岩失稳。依托犬木塘水库大山岭引水隧洞工程,采用数字图像技术对HC法进行修正,可实现对水工隧洞进行精细化围岩分级,为合理的隧洞支护设计提供依据。为此,首先明确了水工隧洞围岩分级HC法中岩石强度采用点荷载试验,岩体完整程度、结构面状态、结构面产状采用数字图像技术进行确定的评分方法;其次,通过对九龙岭隧洞2号支洞的实际应用表明,所取岩体的岩石单轴抗压强度为24.22 MPa、结构面走向与洞轴线夹角为32.5°、结构面倾角为40.1°,结构面充填物主要为岩屑、呈微张状态、起伏较为粗糙,岩体体积节理数3≤Jv≤10;最后,参照《水力发电工程地质勘察规范》,并结合HC法评分准则,评定犬木塘九龙岭2号支洞ZG23+717.5处围岩总评分T为29分,围岩级别为Ⅳ类围岩。该方法具有图像采集便捷、计算过程简洁、分析结果准确等优点,可为水工隧洞开挖支护设计提供重要的决策支持,具有显著的工程实用价值和广泛的应用前景。The existing hydraulic tunnel surrounding rock classification method is still mainly empirical,which is easy to cause deviation of the surrounding rock classification results and lead to irrational tunnel support design,and even surrounding rock destabilization in the excavation process.Relying on the Dashanling diversion tunnel project of Quanmutang Reservoir,this paper adopts the numerical image technology to modify the HC method,which can realize the fine surrounding rock classification of hydraulic tunnels and provide a basis for reasonable tunnel support design.To this end,firstly,the grading method of HC method for hydraulic tunnel surrounding rock classification is clarified by adopting the point load test for rock strength,and the grading method of determining the degree of integrity of the rock body,the state of structural surface,and the yield of structural surface by adopting the numerical image technology.Secondly,the practical application of the Jiulongling Tunnel No.2 branch shows that the uniaxial compressive strength of the rock body taken is 24.22 MPa,the angle of the structural surface strike to the tunnel axis is 32.5 The uniaxial compressive strength of the rock body taken is 24.22 MPa,the angle between the structural plane and the axis of the hole is 32.5°,the inclination of the structural plane is 40.1°,and the filler of the structural plane mainly consists of rock debris,which is in the state of microtension,with a rough undulation and the number of volumetric joints of the rock body is 3≤Jv≤10.Finally,with reference to the“Code for Hydropower Engineering Geological Investigation”,and combining with the scoring guideline of the HC method,the total scoring of surrounding rock at the branch hole No.2 of Jiulongling of Quanmutang,ZG23+717.5,assessed to be 29 points,and the grade of the surrounding rock is classⅣ.The method has the advantages of convenient image acquisition,concise calculation process,and accurate analysis results,etc.It can provide important decision-making support

关 键 词：水工隧洞 掌子面 数字图像 HC法 围岩分级 

分 类 号：U452.12[建筑科学—桥梁与隧道工程]