STUDY OF INFLUENCE OF ROCK STRUCTURE ON SURROUNDING ROCK MASS STABILITY OF UNDERGROUND CAVERNS IN HARD ROCK REGION WITH HIGH GEOSTRESS
LU Bo1，DING Xiuli1，WU Aiqing1，DONG Zhihong1，XIAO Pingxi2，PENG Shixiong2
(1. Key Laboratory of Geotechnical Mechanics and Engineering of the Ministry of Water Resources，Yangtze River Scientific Research Institute，Wuhan，Hubei 430010，China；2. HydroChina Chengdu Engineering Corporation，Chengdu，Sichuan 610072，China)
Abstract：Guandi underground powerhouse is typical deep cavern groups in hard rock region. The challenge is that the geostress in the powerhouse area is high and discontinuities are well developed at the same time. The major principal stress is 25–35 MPa，no regional fault or major weakness zone have been found，but shear zones and joints are well developed. Failure phenomenon of the surrounding rock mass during the excavation of the underground cavern groups has been reviewed thoroughly. Rock structures and failure modes of surrounding rock mass have been studied in full length. The influence of geostress and rock structure on the stability of surrounding rock mass have been investigated in detail. The results show that the rock masses are fresh and belong mainly to class II and have a relative high strength，and so a high strength-stress ratio. The surrounding rock masses has strong ability to resist stress-induced failure. The influence of rock structure on rock masses is relatively stronger than that of geostress. Local instabilities and large deformation of some locations are all controlled by adverse geological discontinuities. In general，the characteristics of the rock structures of machine hall，transformer chamber and surge chamber are similar. This results in the similarity of the deformation characteristics and failure modes of the surrounding rock masses. The three cavers have certain differences in rock structures. Rock structures have different influences on the surrounding rock masses in different caverns，and also the failure modes. Jointed hard rock may assume time-dependent deformation under high geostress and this is another adverse influence of rock structures on rock masses. So，in hard rock regions with high geostress where the strength-stress ratio is high and joints are well developed，the influence of rock structure on surrounding rock masses must be fully considered.
卢 波1，丁秀丽1，邬爱清1，董志宏1，肖平西2，彭仕雄2. 高应力硬岩地区岩体结构对地下洞室围岩稳定的控制效应研究[J]. 岩石力学与工程学报, 2012, 31(s2): 3831-3846.
LU Bo1，DING Xiuli1，WU Aiqing1，DONG Zhihong1，XIAO Pingxi2，PENG Shixiong2. STUDY OF INFLUENCE OF ROCK STRUCTURE ON SURROUNDING ROCK MASS STABILITY OF UNDERGROUND CAVERNS IN HARD ROCK REGION WITH HIGH GEOSTRESS. , 2012, 31(s2): 3831-3846.
[1] HOEK E，BROWN E T. 岩石地下工程[M]. 连志升，田良灿，王维德，等译. 北京：冶金工业出版社，1986：148–196.(HOEK E，BROWN E T. Underground excavation in rock[M]. Translated by LIAN Zhisheng，TIAN Liangcan，WANG Weide，et al. Beijing：Metallurgical Industry Press，1986：148–196.(in Chinese))
[2] 谷兆祺，彭守拙，李仲奎. 地下洞室工程[M]. 北京：清华大学出版社，1994：72–79.(GU Zhaoqi，PENG Shouzhuo，LI Zhongkui. Underground caverns engineering[M]. Beijing：Tsinghua University Press，1994：72–79.(in Chinese))
[3] 董学晟，田 野，邬爱清．水工岩石力学[M]．北京：中国水利水电出版社，2004：390–432(DONG Xuecheng，TIAN Ye，WU Aiqing. Rock mechanics in hydraulic engineering[M]. Beijing：China Water Power Press，2004：390–432.(in Chinese))
[4] 周宏伟，谢和平，左建平. 深部高应力下岩石力学行为研究进展[J].力学进展，2005，35(1)：91–99.(ZHOU Hongwei，XIE Heping，ZUO Jianping. Developments in researches on mechanical behaviors of rocks under the condition of high ground pressure in the depths[J]. Advances in Mechanics，2005，35(1)：91–99.(in Chinese))
[5] 汤 雷，蒋金平. 高地应力条件下围岩稳定性分析及控制[J]. 辽宁工程技术大学：自然科学版，2010，29(1)：24–27.(TANG Lei，JIANG Jinping. Analysis and control on stability of surrounding rock with high ground stress[J]. Journal of Liaoning Technical University：Natural Science，2010，29(1)：24–27.(in Chinese))
[6] 李仲奎，周 钟，汤雪峰，等. 锦屏一级水电站地下厂房洞室群稳定性分析与思考[J]. 岩石力学与工程学报，2009，28(11)：2 167–2 175.(LI Zhongkui，ZHOU Zhong，TANG Xuefeng，et al. Stability analysis and considerations of underground powerhouse caverns group of Jinping I hydropower station[J]. Chinese Journal of Rock Mechanics and Engineering，2009，28(11)：2 167–2 175.(in Chinese))
[7] 卢 波，王继敏，丁秀丽，等. 锦屏一级水电站地下厂房围岩开裂变形机制研究[J]. 岩石力学与工程学报，2010，29(12)：2 429–2 441. (LU Bo，WANG Jimin，DING Xiuli，et al. Study on the deformation and cracking mechanism of the surrounding rock mass of Jinping first stage underground chamber[J]. Chinese Journal of Rock Mechanics and Engineering，2010，29(12)：2 429–2 441.(in Chinese))
[8] 中国水电顾问集团成都勘测设计研究院. 雅砻江官地引水发电系统工程地质报告[R]. 成都：中国水电顾问集团成都勘测设计研究院，2007.(HydroChina Chengdu Engineering Corporation. Engineering geology report on the water diversion and power generation system of Guandi hydropower project located on Yalongjiang River[R]. Chengdu：HydroChina Chengdu Engineering Corporation，2007.(in Chinese))
[9] 中国水电顾问集团成都勘测设计研究院. 雅砻江锦屏一级水电站可行性研究报告[R]. 成都：中国水电顾问集团成都勘测设计研究院，2003.(HydroChina Chengdu Engineering Corporation. Feasibility study report on Jinping I hydropower project located on Yalongjiang River[R]. Chengdu：HydroChina Chengdu Engineering Corporation，2003.(in Chinese))
[10] 丁秀丽，卢 波，黄书岭，等. 雅砻江锦屏一级水电站技施阶段——高应力低强度应力比条件大型地下洞室群围岩开裂变形机制及稳定性研究[R]. 武汉：长江水利委员会长江科学院，2010.3(DING Xiuli，LU Bo，HUANG Shuling，et al. Research on the stability and the fracturing mechanism of the surrounding rock mass for large underground powerhouse group caverns under the conditions of high geostress and low strength-stress ratio[R].Wuhan：Changjiang River Scientific Research Institute，2010.(in Chinese))
[11] 卢 波，董志宏，黄书岭. 雅砻江官地水电站地下厂区洞室群施工期快速监测与反馈分析[R]. 武汉：长江科学院，2011.(LU Bo，DONG Zhihong，HUANG Shuling. Scientific report on the fast measurement and back analysis for the underground powerhouse group caverns construction of Guandi hydropower station located on Yalong River[R]. Wuhan：Yangtze River Scientific Research Institute，2011.(in Chinese))
2012, Vol. 31 
