(1. School of Resource and Safety Engineering，Central South University，Changsha，Hunan 410083，China；
2. Shanghai Hualong Testing Instrument Co.，Ltd.，Shanghai 201202，China)
Abstract：The YJW–20000S microcomputer-controlled hydraulic servo three-directional five-surface loading test system was jointly developed by Central South University and Shanghai Hualong Testing Instrument Co.，Ltd.，to expand the study on mechanical properties of large-scale rock-like materials under high stress conditions. The static and dynamical combination loading，single-face and multi-face unloading tests of large-scale rock specimens can be performed by this system to simulate the mechanical behavior of rock under complex stress conditions such as rock burst. The system?s functionality and accuracy were confirmed through true triaxial fatigue disturbance loading and unloading tests and three-directional five-surface tests on a 400 mm × 400 mm × 400 mm rock-like sample. Uniaxial compression tests on two kinds of large-scale granite specimens，viz. 400 mm × 400 mm × 400 mm and 400 mm × 400 mm × 800 mm，were carried out using this test system. The stress-strain curve characteristics，stress thresholds，size effects and end effects of large-scale granite specimens were analysed. The results show that the four stress thresholds of the large-size granite are the initial microcrack and microporous closure stress(0.37 )，crack-initiation stress(0.54 )，crack-damage stress(0.73 ) and peak strength( )，consistent with the theoretical prediction results of small-scale granite. The compressive strength value of large-scale granite specimen is smaller than the theoretical value based on the size-effect law. Additionally，the axial strain on the transverse section of the specimen?s side gradually decreases from the centre to both sides due to the end effect，and is lower than that in the middle of the specimen. The axial strain value near the side boundary surface of specimen increases with the distance from the end. The farther away from the end，the smaller the axial strain value on the longitudinal section near the centre of the sample's side. Overall，this system can provide reliable technology for in-depth research on the mechanical behavior of large-scale rock specimens under complex stress environments.
赵庆雄1，曹 平1，芦正强2，林 杭1，刘涛影1，李凯辉1，刘智振 1. 20 MN大尺寸岩体三向五面试验系统研制与应用[J]. 岩石力学与工程学报, 2023, 42(8): 1847-1865.
ZHAO Qingxiong1，CAO Ping1，LU Zhengqiang2，LIN Hang1，LIU Taoying1，LI Kaihui1，LIU Zhizhen1. Development of 20 MN large-scale rock mass three-direction five-surface#br#
test system and its application. , 2023, 42(8): 1847-1865.
[1] 吴顺川. 岩石力学[M]. 北京：高等教育出版社，2021：14–15.(WU Shunchuan. Rock mechanic[M]. Beijing：Higher Education Press，2021：14–15.(in Chinese))
[2] 牛学超，张庆喜，岳中文. 岩石三轴试验机的现状及发展趋势[J]. 岩土力学，2013，34(2)：600–607.(NIU Xuechao，ZHANG Qingxi，YUE Zhongwen. Current situation and development trends of rock triaxial testing machine[J]. Rock and Soil Mechanics，2013，34(2)：600–607.(in Chinese))
[3] 葛修润，周百海. 岩石力学室内试验装置的新进展──RMT–64岩石力学试验系统[J]. 岩土力学，1994，15(1)：50–56.(GE Xiurun，ZHOU Baihai. New development of laboratory test equipment for rock mechanics—RMT–64 rock mechanics test system[J]. Rock and Soil Mechanics，1994，15(1)：50–56.(in Chinese))
[4] KWA?NIEWSKI M，LI X，TAKAHASHI M. True triaxial testing of rocks[M]. Leiden，The Netherlands：CRC Press，2012：3‐18.
[5] 张金铸，林天健. 三轴试验中岩石的应力状态和破坏性质[J]. 力学学报，1979，(2)：99–106.(ZHANG Jinzhu，LIN Tianjian. Stress state and failure property of rock in triaxial test[J]. Chinese Journal of Mechanics，1979，(2)：99–106.(in Chinese))
[6] FENG X T，ZHANG X W，KONG R，et al. A novel Mogi type true triaxial testing apparatus and its use to obtain complete stress-strain curves of hard rocks[J]. Rock Mechanics and Rock Engineering，2016，49(5)：1 649–1 662.
[7] 杜 坤，马春德. 大尺寸岩石类材料试件试验系统及应用[C]// 2014年中南地区MTS材料试验学术会议，长沙：[s. n.]，2014：169–177.(DU Kun，MA Chunde. Test system of large size rock-like material specimen and its application[C]// 2014 South Central MTS Materials Testing Conference. Changsha：[s. n.]，2014：169–177.(in Chinese))
[8] 赵阳升. 岩体力学发展的一些回顾与若干未解之百年问题[J]. 岩石力学与工程学报，2021，40(7)：1 297–1 336.(ZHAO Yangsheng. Retrospection on the development of rock mass mechanics and the summary of some unsolved centennial problems[J]. Chinese Journal of Rock Mechanics and Engineering，2021，40(7)：1 297–1 336.(in Chinese))
[9] 李维树，黄书岭，丁秀丽，等. 中尺寸岩样真三轴试验系统研制与应用[J]. 岩石力学与工程学报，2012，31(11)：2 197–2 203.(LI Weishu，HUANG Shuling，DING Xiuli，et al. Development of true triaxial experiment system for middle sized rock sample and its applications[J]. Chinese Journal of Rock Mechanics and Engineering，2012，31(11)：2 197–2 203.(in Chinese))
[10] 隗 敏，许东俊，幸志坚，等. RT3型岩石高压真三轴仪的研制[J]. 岩土力学，1990，11(2)：1–14.(KUI Min，XU Dongjun，XING Zhijian，et al. Development of RT3 type true triaxial apparatus for rock high pressure[J]. Rock and Soil Mechanics，1990，11(2)：1–14.(in Chinese))
[11] 赵 菲. 应变岩爆重要影响因素实验分析[博士学位论文][D]. 北京：中国矿业大学，2015.(ZHAO Fei. Experimental study of important influencing factors for strain rockburst[Ph. D. Thesis][D]. Beijing：China University of Mining and Technology，2015.(in Chinese))
[12] 蒋剑青. 深部隧洞应变型岩爆真三轴试验与动能预测研究[博士学位论文][D]. 南宁：广西大学，2017.(JIANG Jianqing. True triaxial test and kinetic energy prediction study of strained rock burst in deep tunnel[Ph. D. Thesis][D]. Nanning：Guangxi University，2017.(in Chinese))
[13] 许文松. 高应力岩体开挖卸荷扰动效应及巷道围岩控制[博士学位论文][D]. 淮南：安徽理工大学，2019.(XU Wensong. Disturbed effect of excavation unloading and control of surrounding rock of roadway in highly stress rock mass[Ph. D. Thesis][D]. Huainan：Anhui University of Science and Technology，2019.(in Chinese))
[14] 段康廉，赵阳升，胡耀青，等. 1000 t真三轴试验机深基础沉箱法施工技术[J]. 太原理工大学学报，2002，33(2)：157–159.(DUAN Kanglian，ZHAO Yangsheng，HU Yaoqing，et al. The deep-basement sinkbox construction technique of 1000-ton real 3-axis experiment fitment[J]. Journal of Taiyuan University of Technology，2002，33(2)：157–159.(in Chinese))
[15] 任富强. 砂岩双面卸载应变岩爆层理效应实验研究[博士学位论文][D]. 北京：中国矿业大学，2019.(REN Fuqiang. Experimental study of bedding structure for sandstone strain burst when double-sided unloading[Ph. D. Thesis][D]. Beijing：China University of Mining and Technology，2019.(in Chinese))
[16] FENG X T，ZHAO J，ZHANG X W，et al. A novel true triaxial apparatus for studying the time-dependent behaviour of hard rocks under high stress[J]. Rock Mechanics and Rock Engineering，2018，51(9)：2 653–2 667.
[17] 尹立明，郭惟嘉，陈军涛. 岩石应力–渗流耦合真三轴试验系统的研制与应用[J]. 岩石力学与工程学报，2014，33(增1)：2 820– 2 826.(YIN Liming，GUO Weijia，CHEN Juntao. Development of true triaxial rock test system of coupled stress-seepage and its application[J]. Chinese Journal of Rock Mechanics and Engineering，2014，33(Supp.1)：2 820–2 826.(in Chinese))
[18] 尹光志，李铭辉，许 江，等. 多功能真三轴流固耦合试验系统的研制与应用[J]. 岩石力学与工程学报，2015，34(12)：2 436–2 445. (YIN Guangzhi，LI Minghui，XU Jiang，et al. A new multi-functional true triaxial fluid-solid coupling experiment system and its applications[J]. Chinese Journal of Rock Mechanics and Engineering，2015，34(12)：2 436–2 445.(in Chinese))
[19] 张希巍，冯夏庭，孔 瑞，等. 硬岩应力–应变曲线真三轴仪研制关键技术研究[J]. 岩石力学与工程学报，2017，36(11)：2 629– 2 640.(ZHANG Xiwei，FENG Xiating，KONG Rui，et al. Key technology in development of true triaxial apparatus to determine stress-strain curves for hard rocks[J]. Chinese Journal of Rock Mechanics and Engineering，2017，36(11)：2 629–2 640.(in Chinese))
[20] 刘泉声，罗慈友，彭星新，等. 软岩现场流变试验及非线性分数阶蠕变模型[J]. 煤炭学报，2020，45(4)：1 348–1 356.(LIU Quansheng，LUO Ciyou，PENG Xingxin，et al. Research on field rheological test and nonlinear fractional derivative creep model of weak rock mass[J]. Journal of China Coal Society，2020，45(4)：1 348–1 356.(in Chinese))
[21] 刘泉声，罗慈友，陈自由，等. 现场岩体三轴流变试验设备研制[J]. 岩土力学，2018，39(增2)：473–479.(LIU Quansheng，LUO Ciyou，CHEN Ziyou，et al. Development of triaxial rheological testing equipment for in-situ rock mass[J]. Rock and Soil Mechanics，2018，39(Supp.2)：473–479.(in Chinese))
[22] 郑朋强，陈卫忠，谭贤君，等. 软岩大变形巷道底臌破坏机制与支护技术研究[J]. 岩石力学与工程学报，2015，34(增1)：3 143–3 150. (ZHENG Pengqiang，CHEN Weizhong，TAN Xianjun，et al. Research on large-scale triaxial compressive rheological test of soft rock in depth and its constitutive model[J]. Chinese Journal of Rock Mechanics and Engineering，2015，34(Supp.1)：3 143–3 150.(in Chinese))
[23] 陈卫忠，谭贤君，吕森鹏，等. 深部软岩大型三轴压缩流变试验及本构模型研究[J]. 岩石力学与工程学报，2009，28(9)：1 735–1 744. (CHEN Weizhong，TAN Xianjun，LV Sengpeng，et al. Research on large-scale triaxial compressive rheological test of soft rock in depth and its constitutive model[J]. Chinese Journal of Rock Mechanics and Engineering，2009，28(9)：1 735–1 744.(in Chinese))
[24] 张宜虎，周火明，钟作武，等. YXSW–12现场岩体真三轴试验系统及其应用[J]. 岩石力学与工程学报，2011，30(11)：2 312–2 320. (ZHANG Yihu，ZHOU Huoming，ZHONG Zuowu，et al. In situ rock masses triaxial test system YXSW–12 and its application[J]. Chinese Journal of Rock Mechanics and Engineering，2011，30(11)：2 312–2 320.(in Chinese))
[25] 邬爱清. 长江科学院水工岩石力学与工程应用研究进展[J]. 长江科学院院报，2021，38(10)：104–111.(WU Aiqing. Developments of rock mechanics in hydraulic engineering and their applications by yangtze river scientific research institute[J]. Journal of Yangtze River Scientific Research Institute，2021，38(10)：104–111.(in Chinese))
[26] 李维树，周火明，钟作武，等. 岩体真三轴现场蠕变试验系统研制与应用[J]. 岩石力学与工程学报，2012，31(8)：1 636–1 641.(LI Weishu，ZHOU Huoming，ZHONG Zuowu，et al. Development of rock mass true-triaxial site creep testing system and its application[J]. Chinese Journal of Rock Mechanics and Engineering，2012，31(8)：1 636–1 641.(in Chinese))
[27] 夏海城. 基于水力耦合试验与DDA方法的溪洛渡谷幅变形机制研究[硕士学位论文][D]. 武汉：长江科学院，2020.(XIA Haicheng. The research on Xiluodu valley deformation mechanism based on hydraulic coupling test and DDA analysis[M. S. Thesis][D]. Wuhan：Changjiang River Scientific Research Institute，2020.(in Chinese))
[28] 邬爱清，范 雷，钟作武，等. 现场裂隙岩体水力耦合真三轴试验系统研制与应用[J]. 岩石力学与工程学报，2020，39(11)：2 161–2 171.(WU Aiqing，FAN Lei，ZHONG Zuowu，et al. Development of an in situ hydro-mechanical coupling true triaxial test system for fractured rock mass and its application[J]. Chinese Journal of Rock Mechanics and Engineering，2020，39(11)：2 161–2 171.(in Chinese))
[29] 伍法权，乔 磊，管圣功，等. 小尺寸岩样单轴压缩试验尺寸效应研究[J]. 岩石力学与工程学报，2021，40(5)：865–873.(WU Faquan，QIAO Lei，GUAN Shenggong，et al. Uniaxial compression test study on size effect of small size rock samples[J]. Chinese Journal of Rock Mechanics and Engineering，2021，40(5)：865–873.(in Chinese))
[30] 郭育霞，赵永辉，冯国瑞，等. 矸石胶结充填体单轴压缩损伤破坏尺寸效应研究[J]. 矿业研究与开发，2021，40(12)：2 434–2 444. (GUO Yuxia，ZHAO Yonghui，FENG Guorui，et al. Damage size effect of gangue cemented backfill under uniaxial compression[J]. Mining Research and Development，2021，40(12)：2 434–2 444.(in Chinese))
[31] 陈思顺. 岩石单轴压缩条件下的尺寸效应及声发射特征[硕士学位论文][D]. 太原：太原理工大学，2019.(CHEN Sishun. Size effect and acoustic emission characteristics of rock under uniaxial compression[M. S. Thesis][D]. Taiyuan：Taiyuan University of Technology，2019.(in Chinese))
[32] MENG B Q，ZHANG M W，HAN L J，et al. Effects of size and strain rate on the mechanical behaviors of rock specimens under uniaxial compression[J]. Arabian Journal of Geosciences，2016，9(8)：527.
[33] 梁正召，张永彬，唐世斌，等. 岩体尺寸效应及其特征参数计算[J]. 岩石力学与工程学报，2013，32(6)：1 157–1 166.(LIANG Zhengzhao，ZHANG Yongbin，TANG Shibin，et al. Size effect of rock messes and associated representative element properties[J]. Chinese Journal of Rock Mechanics and Engineering，2013，32(6)：1 157–1 166.(in Chinese))
[34] 张后全，徐建峰，贺永年，等. 灰岩单轴压缩实验室尺度效应研究[J]. 岩石力学与工程学报，2012，31(增2)：3 491–3 496.(ZHANG Houquan，XU Jianfeng，HE Yongnian，et al. Laboratory scale effect of uniaxial compression of limestone[J]. Chinese Journal of Rock Mechanics and Engineering，2012，31(Supp.2)：3 491–3 496.(in Chinese))
[35] YOSHINAKA R，OSADA M，PARK H，et al. Practical determination of mechanical design parameters of intact rock considering scale effect[J]. Engineering Geology，2007，96(3/4)：173–186.
[36] LIANG C Y，ZHANG Q B，LI X，et al. The effect of specimen shape and strain rate on uniaxial compressive behavior of rock material[J]. Bulletin of Engineering Geology and the Environment，2016，75(4)：1 669–1 681.
[37] 梁昌玉，李 晓，吴树仁. 中低应变率加载条件下花岗岩尺寸效应的能量特征研究[J]. 岩土力学，2016，37(12)：3 472–3 480.(LIANG Changyu，LI Xiao，WU Shuren. Research on energy characteristics of size effect of granite under low/intermediate strain rates[J]. Rock and Soil Mechanics，2016，37(12)：3 472–3 480.(in Chinese))
[38] 潘鹏志，周 辉，冯夏庭. 加载条件对不同尺寸岩石单轴压缩破裂过程的影响研究[J]. 岩石力学与工程学报，2008，27(增2)：3 636–3 642.(PAN Pengzhi，ZHOU Hui，FENG Xiating. Research on effect of loading conditions on failure processes of rocks with different sizes under uniaxial compression[J]. Chinese Journal of Rock Mechanics and Engineering，2008，27(Supp.2)：3 636–3 642.(in Chinese))
[39] DARLINGTON W，RANJITH P，CHOI S. The effect of specimen size on strength and other properties in laboratory testing of rock and rock-like cementitious brittle materials[J]. Rock Mechanics and Rock Engineering，2011，44(5)：513–529.
[40] 吕兆兴，冯增朝，赵阳升. 岩石的非均质性对其材料强度尺寸效应的影响[J]. 煤炭学报，2007，32(9)：917–920.(LV Zhaoxing，FENG Zengchao，ZHAO Yangsheng. Influence of rock heterogeneity on strength-size effect of rock material[J]. Journal of China Coal Society，2007，32(9)：917–920.(in Chinese))
[41] BROWN E T，HOEK E. Underground excavations in rock[M]. Taylor and Francis：CRC Press，1980：155–156.
[42] CAO R H，LIN H，CAO P. Strength and failure characteristics of brittle jointed rock-like specimens under uniaxial compression：Digital speckle technology and a particle mechanics approach[J]. International Journal of Mining Science and Technology，2018，28(4)：669–677.
[43] YANG H T，LIN H，CHEN Y F，et al. Influence of wing crack propagation on the failure process and strength of fractured specimens[J]. Bulletin of Engineering Geology and the Environment，2022，81(71)：19.
[44] LIN Q B，CAO P，CAO R H，et al. Mechanical behavior around double circular openings in a jointed rock mass under uniaxial compression[J]. Archives of Civil and Mechanical Engineering，2020，20(19)：18.
[45] EBERHARDT E，STEAD D，STIMPSON B. Identifying crack initiation and propagation thresholds in brittle rock[J]. Canadian Geotechnical Journal，1998，35(2)：222–233.
[46] 曹 平. 计算岩石力学[M]. 长沙：中南大学出版社，2016：35.(CAO Ping. Computational rock mechanics[M]. Changsha：Central South University Press，2016：35.(in Chinese))
[47] 张国凯，李海波，夏 祥，等. 单轴加载条件下花岗岩声发射及波传播特性研究[J]. 岩石力学与工程学报，2017，36(5)：1 133–1 144. (ZHANG Guokai，LI Haibo，XIA Xiang，et al. Experiment study on acoustic emission and wave propagation in granite under uniaxial compression[J]. Chinese Journal of Rock Mechanics and Engineering，2017，36(5)：1 133–1 144.(in Chinese))
[48] MARTIN C D，CHANDLER N A. The progressive fracture of Lac du Bonnet granite[J]. International Journal of Rock Mechanics and Mining Science and Geomechanics Abstracts，1994，31(6)：643–659.
[49] BIENIAWSKI Z T. Mechanism of brittle fracture of rock，Part II[J]. International Journal of Rock Mechanics and Mining Sciences and Geomechanics Abstracts，1967，4(4)：407–423.
[50] SCHMIDTKE R H，LAJTAI E Z. The long-term strength of lac du bonnet granite[J]. International Journal of Rock Mechanics and Mining Science and Geomechanics Abstracts，1985，22(6)：461–465.
[51] GERCEK H，ALBRECHT H. Poisson's ratio values for rocks[J]. International Journal of Rock Mechanics and Mining Sciences，2006，44(1)：1–13.
[52] 徐小丽，陈 琳，高 峰，等. 花岗岩的加载速率效应及能量机制研究[J]. 固体力学学报，2015，36(2)：154–163.(XU Xiaoli，CHEN Lin，GAO Feng，et al. Study on loading rate effect and energy mechanism of granite[J]. Chinese Journal of Solid Mechanics，2015，36(2)：154–163.(in Chinese))
[53] 吕森鹏，陈卫忠，贾善坡，等. 脆性岩石破坏试验研究[J]. 岩石力学与工程学报，2009，28(增1)：2 772–2 777.(LV Senpeng，CHEN Weizhong，JIA Shanpo，et al. Experimental study on failure of brittle rock[J]. Chinese Journal of Rock Mechanics and Engineering，2009，28(Supp.1)：2 772–2 777.(in Chinese))
[54] HUDSON J A，BROWN E T，FAIRHURST C. Shape of the complete stress-strain curve for rock[J]. Proceedings of the 13th Symposium on Rock Mechanics，1971，1(11)：773–795.
[55] 张春生，陈祥荣，侯 靖，等. 锦屏二级水电站深埋大理岩力学特性研究[J]. 岩石力学与工程学报，2010，29(10)：1 999–2 009. (ZHANG Chunsheng，CHEN Xiangrong，HOU Jing，et al. Study of mechanical behavior of deep-buried marble at Jinping Ⅱ hydropower station[J]. Chinese Journal of Rock Mechanics and Engineering，2010，29(10)：1 999–2 009.(in Chinese))
[56] 杨圣奇，苏承东，徐卫亚. 岩石材料尺寸效应的试验和理论研究[J]. 工程力学，2005，(4)：112–118.(YANG Shengqi，SU Chengdong，XU Weiya. Experimental and theoretical study on size effect of rock materials[J]. Engineering Mechanics，2005，(4)：112–118.(in Chinese))
[57] 范鹏贤，王贾博，刘家贵，等. 端部条件对红砂岩试件测试强度影响的试验研究[J]. 应用基础与工程科学学报，2021，29(2)：426–437.(FAN Pengxian，WANG Jiabo，LIU Jiagui，et al. The influence of end condition on the test strength of red sandstone samples[J]. Journal of Basic Science and Engineering，2021，29(2)：426–437.(in Chinese))
[58] 吴志酬. 硬岩强度的端部效应及泊松比的试验测试方法[硕士学位论文][D]. 南京：南京理工大学，2020.(WU Zhichou. The end effect of rock strength and the experimental determination of Poisson?s ratio[M. S. Thesis][D]. Nanjing：Nanjing University of Science and Technology，2020.(in Chinese))
[59] HAWKES I，MELLOR M. Uniaxial testing in rock mechanics laboratories[J]. Engineering Geology，1970，4(3)：179–285.
[60] 白世伟，林世胜，朱维申. 单轴压缩圆柱状岩石试件应力分布均匀性的研究[J]. 岩土工程学报，1982，4(4)：193–203.(BAI Shiwei，LIN Shisheng，ZHU Weishen. Uniformity of stress distribution in rock cylindrical specimens under uniaxial compression[J]. Chinese Journal of Geotechnical Engineering，1982，4(4)：193–203.(in Chinese))
[61] JAEGER J C，COOK N G W. Fundamentals of rock mechanics[M]. London，New York：Chapman and Hall，1979：18.
2023, Vol. 42 
