(1. School of Civil Engineering,Central South University,Changsha,Hunan 411075,China;2. China Railway No.5 Engineering Group Co.,Ltd.,Changsha,Hunan 410007,China)
Abstract:To investigate the impact of high-temperature water on gneiss characteristics,the uniaxial compression and Brazilian splitting tests under various high-temperature water bath conditions were performed. Subsequently,the evolution mechanisms of mechanical properties and macroscopic failure characteristics of gneiss were analyzed. Meanwhile,the acoustic emission(AE) monitoring technology,X-ray diffraction(XRD) and scanning electron microscopy(SEM) were utilized to explore the microscopic mechanism of rock failure. The experimental findings reveal that high-temperature water baths significantly diminish the mechanical properties of gneiss,with a more pronounced effect observed with increased water bath time and temperature. Additionally,the failure mode of rocks is also impacted. As the water bath time increases,the failure mode of gneiss transitions from single oblique shear failure to compressive conical shear failure and eventually to shear failure accompanied by tensile cracks,under the conditions of no water bath at room temperature,water bath at 60 ℃ and 92.6 ℃. Moreover,high-temperature water accelerates the weakening effect of the mechanical properties of gneiss compared with room temperature water immersion. This research provides essential theoretical support and engineering guidance for tunnel construction and disaster prevention in high-temperature water environments.
[1] 何 平,张广泽,强新刚. 川藏线桑珠岭隧道地下热水成因及选线研究[J]. 铁道工程学报,2020,37(6):10–13.(HE Ping,ZHANG Guangze,QIANG Xingang. Cause analysis of geothermal water and geological route selection research on the Sangzhuling Tunnel of Sichuan-Tibet Railway[J]. Journal of Railway Engineering Society,2020,37(6):10–13.(in Chinese))
[2] 李有能. 吉沃希嘎隧道地热预测物探方法研究[J]. 铁道建筑技术,2015,(10):1–4.(LI Youneng. Geophysical prospecting techniques for geothermal prediction in the Jiwoxiga Tunnel[J]. Railway Construction Technology,2015,(10):1–4.(in Chinese))
[3] 姚显春,李 宁,余春海,等. 新疆公格尔高温引水隧洞围岩温度场试验研究[J]. 水文地质工程地质,2018,45(4):59–66.(YAO Xianchun,LI Ning,YU Chunhai,et al. Filed test of temperature field of the surrounding rocks of high temperature in the Gonggerer diversion tunnel in Xiniiang[J]. Hydrogeology Engineering Geology,2018,45(4):59–66.(in Chinese))
[4] 刘泉声,许锡昌. 温度作用下脆性岩石的损伤分析[J]. 岩石力学工程学报,2000,19(4):408–411.(LIU Quansheng,XU Xichang. Damage analysis of brittle rock at high temperature[J]. Chinese Journal of Rock Mechanics and Engineering,2000,19(4):408–411.(in Chinese))
[5] 许锡昌,刘泉声. 高温下花岗岩基本力学性质初步研究[J]. 岩土工程学报,2000,22(3):332–335.(XU Xichang,LIU Quansheng. A preliminary study on basic mechanical properties for granite at high temperature[J]. Chinese Journal of Geotechnical Engineering,2000,22(3):332–335.(in Chinese))
[6] 徐小丽,高 峰,张志镇,等. 实时高温下加载速率对花岗岩力学特性影响的试验研究[J]. 岩土力学,2015,36(8):2 184–2 192.(XU Xiaoli,GAO Feng,ZHANG Zhizhen,et al. Experimental study of the effect of loading rates on mechanical properties of granite at real-time high temperature[J]. Rock and Soil Mechanics,2015,36(8):2 184–2 192.(in Chinese))
[7] 徐小丽,高 峰,沈晓明,等. 高温后花岗岩力学性质及微孔隙结构特征研究[J]. 岩土力学,2010,31(6):1 752–1 758.(XU Xiaoli,GAO Feng,SHEN Xiaoming,et al. Research on mechanical characteristics and micropore structure of granite under high-temperature[J]. Rock and Soil Mechanics,2010,31(6):1 752–1 758.(in Chinese))
[8] 徐小丽,高 峰,张志镇,等. 高温作用后花岗岩三轴压缩试验研究[J]. 岩土力学,2014,35(11):3 177–3 183.(XU Xiaoli,GAO Feng,ZHANG Zhizhen,et al. Research on triaxial compression test of granite after high temperatures[J]. Rock and Soil Mechanics,2014,35(11):3 177–3 183.(in Chinese))
[9] SINGH B,RANJITH P G,CHANDRASEKHARAM D,et al. Thermomechanical properties of Bundelkhand granite near Jhansi,India[J]. Geomechanics and Geophysics for Geo-Energy and Geo-Resources,2015,(1):35–53.
[10] 黄彦华,陶 然,陈 笑,等. 高温后花岗岩断裂特性及热裂纹演化规律研究[J]. 岩土工程学报,2023,45(4):739–747.(HUANG Yanhua,TAO Ran,CHEN Xiao,et al. Fracture behavior and thermal cracking evolution law of granite specimens after high-temperature treatment[J]. Chinese Journal of Geotechnical Engineering,2023,45(4):739–747.(in Chinese))
[11] DWIVEDIA R D,GOELA R K,PRASADA V V R,et al. Thermomechanical properties of Indian and other granites[J]. International Journal of Rock Mechanics and Mining Sciences,2008,45:303–315.
[12] 查文华,宋新龙,武腾飞. 不同温度条件下煤系砂质泥岩力学特征试验研究[J]. 岩石力学与工程学报,2014,33(4):809–816.(ZHA Wenhua,SONG Xinlong,WU Tengfei. Experimental study of mechanical characteristics of coal-serial sandy mudstone at different temperatures[J]. Chinese Journal of Rock Mechanics and Engineering,2014,33(4):809–816.(in Chinese))
[13] MA X,WANG Z L,HU D W,et al. Mechanical properties of granite under real-time high temperature and three-dimensional stress[J]. International Journal of Rock Mechanics and Mining Sciences,2020,136:104521.
[14] KUMARI W G P,RANJITHA P G,PERERA M S A,et al. Mechanical behaviour of Australian Strathbogie granite under in-situ stress and temperature conditions:An application to geothermal energy extraction[J]. Geothermics,2017,65:44–59.
[15] ZHOU Z L,CAI X,MA D,et al. Water saturation effects on dynamic fracture behavior of sandstone[J]. International Journal of Rock Mechanics and Mining Sciences,2019,114:46–61.
[16] ZHOU Z L,CAI X,CAO W,et al. Influence of water content on mechanical properties of rock in both saturation and drying processes[J]. Rock Mechanics Rock Engineering,2016,49:3 009–3 025.
[17] ZHOU Z L,CAI X,ZHAO Y,et al. Strength characteristics of dry and saturated rock at different strain rates[J]. Transactions of Nonferrous Metals Society of China,2016,7:1 919–1 925.
[18] CAI X,CHENG C,ZHAO Y,et al. The role of water content in rate dependence of tensile strength of a fine-grained sandstone[J]. Archives of Civil and Mechanical Engineering,2022,22:58.
[19] CAI X,ZHOU Z L,ZANG H Z,et al. Water saturation effects on dynamic behavior and microstructure damage of sandstone:Phenomena and mechanisms[J]. Engineering Geology,2020,276:105760.
[20] CAI X,ZHOU Z L,DU X M. Water-induced variations in dynamic behavior and failure characteristics of sandstone subjected to simulated geo-stress[J]. International Journal of Rock Mechanics and Mining Sciences,2020,130:104339.
[21] ERGULER Z A,ULUSAY R. Water-induced variations in mechanical properties of clay-bearing rocks[J]. International Journal of Rock Mechanics and Mining Sciences,2009,46(2):355–370.
[22] TÖRÖK Á,VÁSÁRHELYI B. The influence of fabric and water content on selected rock mechanical parameters of travertine,examples from Hungary[J]. Engineering Geology,2010,115(3/4):237–245.
[23] YILMAZ I. Influence of water content on the strength and deformability of gypsum[J]. International Journal of Rock Mechanics and Mining Sciences,2010,47(2):342–347.
[24] VUTUKURI V S. The effect of liquids on the tensile strength of limestone[J]. International Journal of Rock Mechanics and Mining Sciences and Geomechanics Abstracts,1974,11(1):27–29.
[25] WONG L N Y,MING C J. Water saturation effects on the Brazilian tensile strength of gypsum and assessment of cracking processes using high-speed video[J]. Rock Mechanics and Rock Engineering,2014,47(4):1 103–1 115.
[26] HASHIBA K,FUKUI K. Effect of water on the deformation and failure of rock in uniaxial tension[J]. Rock Mechanics and Rock Engineering,2015,48(5):1 751–1 761.
[27] HABERFIELD C M,JOHNSTON I W. Determination of the fracture toughness of a saturated soft rock[J]. Canadian Geotechnical Journal,1990,27(3):276–284.
[28] LIM I L,JOHNSTON I W,CHOI S K,et al. Fracture testing of a soft rock with semi-circular specimens under three-point bending. Part 1—mode I[J]. International Journal of Rock Mechanics and Mining Sciences and Geomechanics Abstracts,1994,31(3):185–197.
[29] OHNO K,OHTSU M. Crack classification in concrete based on acoustic emission[J]. Construction and Building Materials,2010,24(12):2 339–2 346.
[30] 周其健,马德翠,邓荣贵,等. 地热系统作用下红层软岩力学性能试验研究[J]. 岩土力学,2020,41(10):3 333–3 342.(ZHOU Qijian,MA Decui,DENG Ronggui,et al. Experimental study on mechanical properties of red-layer soft rock in geothermal systems[J]. Rock and Soil Mechanics,2020,41(10):3 333–3 342.(in Chinese))