摘要
抽水蓄能电站建设处于加速期,合理布置地应力试验和精准获取地应力数据对高水头抽水蓄能电站意义重大。以某高水头抽水蓄能电站为案例,针对高水头抽水蓄能电站地形特点及地应力特征,在不同勘察阶段进行综合地应力测量,同时联合地应力场反演,获取空间三维地应力场分布规律并对围岩进行抗劈裂分析。综合实测结果表明:二维地表深孔结果随埋深梯度有变化,中浅部有应力集中现象,符合高水头抽水蓄能电站的地应力分布特征。三孔交汇法及孔壁应变法的地应力量值及方向吻合,地下厂房和高压岔管部位岩体的最大实测主应力为20.9 MPa,最小主应力为7.0 MPa;岩体以水平应力为主。最大主应力方向集中为NEE向。有利用综合实测结果加强模型精细化进行初始地应力场反演,能较好地反映此类工程的地应力场特征,利于围岩的抗劈裂分析及后续衬砌方案的选择。综合地应力测试对于高水头抽水蓄能的地应力获取具有可行性。可供高水头抽水蓄能电站工程的地应力勘察参考。
The accelerated construction of pumped storage power stations underscores the importance of reasonable arrangement in-situ stress testing and precise data acquisition for high-head pumped storage power stations.This study,taking a high-head pumped storage power station as an example,conducted comprehensive in-situ stress measurements across various survey stages,considering the topographic and in-situ stress characteristics.By integrating in-situ stress field inversion,we obtained the spatial three-dimensional in-situ stress field distribution and analyzed the anti-splitting properties of the surrounding rock.The comprehensive measurements revealed that the two-dimensional surface deep hole results vary with the buried depth gradient,exhibiting stress concentration in the middle and shallow regions,aligning with the in-situ stress distribution patterns of high-head pumped storage power stations.The maximum measured principal stress in the underground plant and high-pressure bifurcation pipe reached 20.9 MPa,while the minimum principal stress was 7.0 MPa,indicating that horizontal stress is the dominant stress in the rock mass.The maximum principal stress direction is concentrated towards the NEE orientation.The inversion of the initial in-situ stress field can be carried out by using the comprehensive measured results to strengthen the refinement of the model,which can better reflect the characteristics of the in-situ stress field of such projects,and is conducive to the anti-splitting analysis of the surrounding rock and the selection of subsequent lining schemes.This study demonstrates the feasibility of comprehensive in-situ stress testing for high-head pumped storage projects,providing a valuable reference for in-situ stress investigations in such power station projects.
作者
韩晓玉
郑炜烽
董志宏
张新辉
HAN Xiao-yu;ZHENG Wei-feng;DONG Zhi-hong;ZHANG Xin-hui(Key Laboratory of Geotechnical Mechanics and Engineering,Ministry of Water Resources,Yangtze River Science Institute,Wuhan,Hubei 430071,China;College of Civil Engineering and Architecture,China Three Gorges University,Yichang,Hubei 443000,China)
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2024年第7期2167-2174,共8页
Rock and Soil Mechanics
基金
云南省重大科技专项计划项目(No.202002AF080003,No.202102AF080001)
中央级公益性科研院所基本科研业务费项目(No.CKSF2021462/YT,No.CKSF2023308/YT,No.CKSF2023316/YT)。
关键词
综合地应力测试
地应力场反演
抗劈裂分析
comprehensive in-situ stress test
in-situ stress field inversion
anti-cracking analysis
