Experimental study on dynamic strength characteristics of fractured rocks under high water pressure and high stress
JIN Jiefang1,LIAO Qiangqiang1,CHEN Meng2,XIONG Huiying1,XIAO Youfeng1,PENG Xiaowang1
(1. School of Civil and Surveying Engineering,Jiangxi University of Science and Technology,Ganzhou,Jiangxi 341000,China;2. School of Resource and Environment Engineering,Jiangxi University of Science and Technology,
Ganzhou,Jiangxi 341000,China)
Abstract:Numerous pre-existing fractures within deep engineered rock masses and the complex hydraulic environment,significantly affect the dynamic strength characteristics of these engineered rock masses. To investigate the effects of fractures and high water pressure on the dynamic strength characteristics of rocks,five types of red sandstone specimens with different fracture inclination angles were prepared. Impact tests were carried out under six water pressure gradients using a self-developed rock dynamics testing device capable of simulating high water pressure and high geo-stress conditions. The results indicate that with the increase of water pressure and fracture inclination angle,the dynamic stress-strain curve of the fractured rock is gradually transformed from plastic to elastic after-effects after the peak. The curve characteristics can be categorized into three stages. When the fracture inclination angle is fixed,the dynamic peak stress of the fractured rock initially increases with rising water pressure,followed by a slight decreases. The relationship between dynamic peak stress and water pressure follows a Gaussian distribution. As water pressure increases,the average strain rate first decreases and then increases. Under the same water pressure,the dynamic peak stress of fractured rock generally exhibits a trend of slow initial increase followed by a rapid rise as the fracture inclination angle increases,and this trend is influenced by the radial connectivity of the fractured rock and the oblique incidence of stress waves. Moreover,the average strain rate gradually decreases with the increase of fracture inclination angle. A clear negative linear relationship is observed between the dynamic peak stress of the fractured rock and the average strain rate.
金解放1,廖强强1,陈 萌2,熊慧颖1,肖莜丰1,彭孝旺1. 高水压高应力裂隙岩石动态强度特性试验研究[J]. 岩石力学与工程学报, 2025, 44(5): 1133-1145.
JIN Jiefang1,LIAO Qiangqiang1,CHEN Meng2,XIONG Huiying1,XIAO Youfeng1,PENG Xiaowang1. Experimental study on dynamic strength characteristics of fractured rocks under high water pressure and high stress. , 2025, 44(5): 1133-1145.
[1] 夏开文,王 帅,徐 颖,等. 深部岩石动力学实验研究进展[J]. 岩石力学与工程学报,2021,40(3):448–475.(XIA Kaiwen,WANG Shuai,XU Ying,et al. Advances in experimental studies for deep rock dynamics[J]. Chinese Journal of Rock Mechanics and Engineering,2021,40(3):448–475.(in Chinese)).
[2] 谢和平,李存宝,高明忠,等. 深部原位岩石力学构想与初步探索[J]. 岩石力学与工程学报,2021,40(2):217–232.(XIE Heping,LI Cunbao,GAO Mingzhong,et al. Conceptualization and preliminary research on deep in situ rock mechanics[J]. Chinese Journal of Rock Mechanics and Engineering,2021,40(2):217–232.(in Chinese))
[3] LI D,GAO F,HAN Z,et al. Experimental evaluation on rock failure mechanism with combined flaws in a connected geometry under coupled static-dynamic loads[J]. Soil Dynamics and Earthquake Engineering,2020,132:106088.
[4] MA Q,SU Q,YUAN P. Dynamic behavior and energy evolution characteristic of deep roadway sandstone containing weakly filled joint at various angles[J]. Advances in Civil Engineering,2020,2020(1):8817107.
[5] 袁 伟,李建春,李 星. 非充填岩石节理的动态剪切力学行为实验研究进展[J]. 力学与实践,2023,45(5):960–971.(YUAN Wei,LI Jianchun,LI Xing. Progress of experimental study on dynamic shear behaviors of unfilled rock joints[J]. Mechanics in Engineering,2023,45(5):960–971.(in Chinese))
[6] JIANG Y X,WU D,ZHAO X Z,et al. Experimental and numerical study on the damage evolution and acoustic emission multi-parameter responses of single flaw sandstone under uniaxial compression[J]. Theoretical and Applied Fracture Mechanics,2024,133(PA):133:104535.
[7] FENG P,XU Y,DAI F. Effects of dynamic strain rate on the energy dissipation and fragment characteristics of cross-fissured rocks[J]. International Journal of Rock Mechanics and Mining Sciences,2021,138:104600.
[8] FENG P,ZHAO J,DAI F,et al. Mechanical behaviors of conjugate-flawed rocks subjected to coupled static-dynamic compression[J]. Acta Geotechnica,2022,17(5):1 765–1 784.
[9] 李地元,韩震宇,孙小磊,等. 含预制裂隙大理岩SHPB动态力学破坏特性试验研究[J]. 岩石力学与工程学报,2017,36(12): 2 872–2 883.(LI Diyuan,HAN Zhenyu,SUN Xiaolei,et al. Characteristics of dynamic failure of marble with artificial flaws under split Hopkinson pressure bar tests[J]. Chinese Journal of Rock Mechanics and Engineering,2017,36(12):2 872–2 883.(in Chinese))
[10] 李地元,胡楚维,朱泉企. 预制裂隙花岗岩动静组合加载力学特性和破坏规律试验研究[J]. 岩石力学与工程学报,2020,39(6): 1 081–1 093.(LI Diyuan,HU Chuwei,ZHU Quanqi. Experimental study on mechanical properties and failure laws of granite with an artificial flaw under coupled static and dynamic loads[J]. Chinese Journal of Rock Mechanics and Engineering,2020,39(6):1 081–1 093.(in Chinese))
[11] LI X B,ZHOU T,LI D Y. Dynamic strength and fracturing behavior of single-flawed prismatic marble specimens under impact loading with a split-Hopkinson pressure bar[J]. Rock Mechanics and Rock Engineering,2016,50:29–44.
[12] YOU W,DAI F,LIU Y,et al. Dynamic mechanical responses and failure characteristics of fractured rocks with hydrostatic confining pressures:An experimental study[J]. Theoretical and Applied Fracture Mechanics,2022,122:103570.
[13] 方 杰,姚强岭,王伟男,等. 含水率对泥质粉砂岩强度损伤及声发射特征影响的研究[J]. 煤炭学报,2018,43(增2):412–419. (FANG Jie,YAO Qiangling,WANG Weinan,et al. Experimental study on damage characteristics of siltstone under water action[J]. Journal of China Coal Society,2018,43(Supp.2):412–419.(in Chinese))
[14] 于超云,唐世斌,唐春安. 含水率对红砂岩瞬时和蠕变力学性质影响的试验研究[J]. 煤炭学报,2019,44(2):473–481.(YU Chaoyun,TANG Shibin,TANG Chun?an. Experimental investigation on the effect of water content on the short-term and creep mechanical behaviors of red sandstone[J]. Journal of China Coal Society,2019,44(2):473–481.(in Chinese))
[15] 邓华锋,齐 豫,李建林,等. 水–岩作用下断续节理砂岩力学特性劣化机制[J]. 岩土工程学报,2021,43(4):634–643.(DENG Huafeng,QI Yu,LI Jianlin,et al. Degradation mechanism of intermittent jointed sandstone under water-rock interaction[J]. Chinese Journal of Geotechnical Engineering,2021,43(4):634–643.(in Chinese))
[16] ZHOU Z,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.
[17] 平 琦,孙施佳,高 祺,等. 饱水裂隙砂岩动态力学特性与裂纹扩展规律研究[J]. 岩石力学与工程学报,2024,43(增1):3 131–3 139.(PING Qi,SUN Shijia,GAO Qi,et al. Study on dynamic mechanical properties and crack extension law of water-saturated fractured sandstone[J]. Chinese Journal of Rock Mechanics and Engineering,2024,43(Supp.1):3 131–3 139.(in Chinese))
[18] 金解放,孙俊涛,杨洪灏. 高水压对红砂岩动态强度和变形特性影响的试验研究[J]. 岩石力学与工程学报,2023,42(10):2 372– 2 384.(JIN Jiefang,SUN Juntao,YANG Honghao. Experimental investigation on the influence of high water pressure on dynamic strength and deformation characteristics of red sandstone[J]. Chinese Journal of Rock Mechanics and Engineering,2023,42(10):2 372–2 384.(in Chinese))
[19] 金解放,杨洪灏,孙俊涛. 高水压对岩石动态能量耗散和破坏特性的影响[J]. 煤炭学报,2023,48(增2):563–574.(JIN Jiefang,YANG Honghao,SUN Juntao. Influence of high water pressure on dynamic energy dissipation and failure characteristics of rock[J]. Journal of China Coal Society,2023,48(Supp.2):563–574.(in Chinese))
[20] 金解放,方立兴,王 宇,等. 高水压高应力岩石动态响应特性试验研究[J]. 岩石力学与工程学报,2024,43(8):1 821–1 838. (JIN Jiefang,FANG Lixing,WANG Yu,et al. Experimental study on dynamic response characteristics of rocks under high water pressure and high stress[J]. Chinese Journal of Rock Mechanics and Engineering,2024,43(8):1 821–1 838.(in Chinese))
[21] ZHOU Y X,XIA K,LI X B,et al. Suggested methods for determining the dynamic strength parameters and mode–I fracture toughness of rock materials[J]. International Journal of Rock Mechanics and Mining Sciences,2012,49:105–112.
[22] DING S,TANG S. Mechanical behavior evolution and failure characteristics of saturated and dry rocks under different water pressure environments[J]. International Journal of Rock Mechanics and Mining Sciences,2024,178:105777.
[23] WASANTHA P L P,RANJITH P G. Water-weakening behavior of Hawkesbury sandstone in brittle regime[J]. Engineering Geology,2014,178:91–101.
[24] 金解放,黄方博,赵康艳,等. 高水压高应力岩石声波传播频域特性试验研究[J]. 岩石力学与工程学报,2024,43(6):1 316–1 334. (JIN Jiefang,HUANG Fangbo,ZHAO Kangyan,et al. Experimental study on acoustic propagation spectrum characteristics of rocks under high water pressure and high stress[J]. Chinese Journal of Rock Mechanics and Engineering,2024,43(6):1 316–1 334.(in Chinese))
[25] 潘 博,汪旭光,徐振洋,等. 节理角度对岩石材料的动态响应影响研究[J]. 岩石力学与工程学报,2021,40(3):566–575. (PAN Bo,WANG Xuguang,XU Zhenyang. Research on the effect of joint angle on dynamic responses of rock materials[J]. Chinese Journal of Rock Mechanics and Engineering,2021,40(3):566–575.(in Chinese))
[26] 刘立波,李建春,李海波,等. 应力波斜入射黏弹性节理的传播规律[J]. 岩石力学与工程学报,2012,31(增2):3 593–3 598. (LIU Libo,LI Jianchun,LI Haibo,et al. Propagation law of oblique incidence of stress wave across a viscoelastic joint[J]. Chinese Journal of Rock Mechanics and Engineering,2012,31(Supp.2):3 593–3 598. (in Chinese))
[27] 王礼立. 应力波基础[M]. 2版. 北京:国防工业出版社,2005:311–317.(WANG Lili. Foundation of stress waves[M]. 2nd ed. Beijing:National Defense Industry Press,2005:311–317.(in Chinese))
[28] YAN Z,DAI F,LIU Y,et al. Dynamic strength and cracking behaviors of single-flawed rock subjected to coupled static-dynamic compression[J]. Rock Mechanics and Rock Engineering,2020,53:4 289–4 298.