Failure mechanism, dynamic characteristics and fracture damage model of grouting reinforced fissured sandstone
WANG Zhide1, AN Jiaxing1, YANG Senlin1, CHEN Cheng1*, XIA Yuanyou1, LIN Manqing2
(1. School of Civil Engineering and Architecture, Wuhan University of Technology, Wuhan, Hubei 430074, China; 2. School of Resources and Safety Engineering, Wuhan Institute of Technology, Wuhan, Hubei 430071, China)
Abstract：To investigate the effects of fracture width and grouting reinforcement on the dynamic mechanical properties of sandstone under blast loading, the split Hopkinson pressure bar(SHPB) impact test, combined with high-speed photography, can be utilized to investigate the dynamic mechanical properties of intact sandstone, fractured sandstone with varying crack widths, and grout-reinforced fractured sandstone under blast loading. Based on fracture mechanics theory, the stress intensity factors of various rock specimens were evaluated, and a dynamic constitutive model was established. The results indicate that: (1) fractured sandstone exhibit a failure mode primarily characterized by shear, supplemented by tensile failure. Following grouting, the failure pattern transitions to predominantly axial tension, accompanied by secondary radial tension, with a significantly reduced degree of damage. As the grout absorbs and reflects a substantial portion of the stress waves, the failure becomes concentrated within the grout itself, considerably enhancing the deformation resistance of the rock mass. Furthermore, this reinforcement effect is progressively amplified with an increase in grout width. (2) The absolute strength degradation coefficient Rs and the absolute strength restoration coefficient Rx were defined. It was observed that both Rs and Rx decrease linearly as fracture width increases. Similarly, the dynamic compressive strength exhibits a linear decline with increasing fracture width, while the peak strain demonstrates a linear upward trend. Grouting significantly enhances the dynamic compressive strength of fractured rock masses and effectively suppresses their peak strain. (3) An increase in fracture width results in a rise in the energy reflection coefficient and a decline in the transmission coefficient. The energy dissipation ratio exhibits a non-monotonic trend—initially increasing and then decreasing—reaching its maximum at a critical width of 5.83 mm. After grouting, the curves for transmitted and reflected energy tend to stabilize, indicating improved energy transmission efficiency. The grout substantially optimizes the energy absorption efficiency of the rock mass, and the dissipated energy increases monotonically with fracture width. (4) Calculated stress intensity factors increase with fracture width but decrease post-grouting. The dynamic constitutive model, which incorporates strain equivalence, Weibull distribution, and the TCK model, demonstrates good agreement with experimental curves.
[1] HU Y G，LU W B，WU X X，et al. Numerical and experimental investigation of blasting damage control of a high rock slope in a deep valley[J]. Engineering Geology，2018，237：12–20.
[2] CHEN J K，GAO W X，HAO X J，et al. Multilateral boundary blasting theory of high and steep slope in open pit mine and its application[C]// Proceedings of the 8th International Conference on Civil Engineering. Singapore：Springer Singapore，2022，213：347–357.
[3] YAO N，ZHANG W H，LUO B Y，et al. Exploring on grouting reinforcement mechanism of expansive slurry[J]. Rock Mechanics and Rock Engineering，2023，56(6)：4 613–4 627.
[4] LI S，ZHANG D，WANG J. Research on the effect of grouting on the stability of fractured rock slopes under blasting load[J]. Journal of Rock Mechanics and Geotechnical Engineering，2019，11(5)：1 047–1 056.
[5] JIANG Z，XU C. Stability analysis and reinforcement technology of fractured rock slopes using grouting methods[J]. Geotechnical Testing Journal，2020，43(4)：615–628.
[6] CHEN Y，WANG F，LI Q. Mitigating blasting-induced vibrations on rock slopes through grouting reinforcement techniques[J]. International Journal of Rock Mechanics and Mining Sciences，2018，107：263–271.
[7] ZHANG H，LIU Y，CHEN X. Numerical simulation of grouting effects on fractured rock slopes subjected to dynamic loading[J]. Computers and Geotechnics，2021，132：103924.
[8] XIE X K，LI J C，ZHENG Y L. Experimental study on dynamic mechanical and failure behavior of a jointed rock mass[J]. International Journal of Rock Mechanics and Mining Sciences，2023，168：105415.
[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] LI D Y，HAN Z Y，SUN X L，et al. Dynamic mechanical properties and fracturing behavior of marble specimens containing single and double flaws in SHPB tests[J]. Rock Mechanics and Rock Engineering，2019，52(6)：1 623–1 643.
[11] LI J C，RONG L F，LI H B，et al. An SHPB test study on stress wave energy attenuation in jointed rock masses[J]. Rock Mechanics and Rock Engineering，2019，52(2)：403–420.
[12] 胡少银，刘泉声，李世辉，等. 裂隙岩体注浆理论研究进展及展望[J]. 煤炭科学学报，2022，50(1)：112–126.(HU Shaoying，LIU Quansheng，LI Shihui，et al. Advanced and review on grouting critical problems in fractured rock mass[J]. Coal Science and Technology，2022，50(1)：112–126.(in Chinese))
[13] 刘泉声，雷广峰，卢超波，等. 注浆加固对岩体裂隙力学性质影响的试验研究[J]. 岩石力学与工程学报，2017，36(增1)：3 140–3 147. (LIU Quansheng，LEI Guangfeng，LU Chaobo，et al. Experimental study of grouting reinforcement influence on mechanical properties of rock fracture[J]. Chinese Journal of Rock Mechanics and Engineering，2017，36(Supp.1)：3 140–3 147.(in Chinese))
[14] 刘人太，郑 卓，李术才，等. 破碎岩体注浆加固后的力学特性研究[J]. 中国公路学报，2018，31(10)：284–291.(LIU Rentai，ZHEN Zhuo，LI Shucai，et al. Mechanical properties of fractured rock mass with consideration of grouting reinforcement[J]. Chinese Journal of Highway Transportation，2018，31(10)：284–291.(in Chinese))
[15] 刘学伟，王 赛，刘 滨，等. 不同注浆材料填充双裂隙类岩石试样力学特性研究[J]. 岩石力学与工程学报，2024，43(3)：623–638.(LIU Xuewei，WANG Sai，LIU Bin，et al. Effect of filling grouting material on mechanical properties and mechanism of rock-like samples with double-crack[J]. Chinese Journal of Rock Mechanics and Engineering，2024，43(3)：623–638.(in Chinese))
[16] 王 志，李 龙，王朝雅. 含裂隙类岩石注浆加固后破坏试验研究[J]. 中南大学学报：自然科学版，2018，49(4)：957–963.(WANG Zhi，LI Long，WANG Chaoya. Experimental study on failure of cracked rock-like material after grouting reinforcement[J]. Journal of Central South University：Science and Technology，2018，49(4)：957–963. (in Chinese))
[17] 杨文轩，王 磊，马飞飞，等. 裂隙注浆砂岩冲击破坏及能量耗散机制[J]. 工程爆破，2025，31(1)：34–41.(YANG Wenxuan，WANG Lei，MA Feifei，et al. The impact failure and energy dissipation mechanism of grouted sandstone in fractures[J]. Engineering Blasting，2025，31(1)：34–41.(in Chinese))
[18] 詹金武，李 涛. 破碎泥岩注浆结石体动力特性的SHPB试验及其数值模拟研究[J]. 岩土力学，2017，38(7)：2 096–2 102.(ZHAN Jinwu，LI Tao. SHPB tests and numerical simulation of dynamic behavior of grouting-reinforced fractured mudstone[J]. Rock and Soil Mechanics，2017，38(7)：2 096–2 102.(in Chinese))
[19] 陈军涛，喻军健，李 果，等. 含不同裂隙数量砂岩注浆前后力学特性试验研究[J]. 岩石力学与工程学报，2025，44(7)：1 767–1 781. (CHEN Juntao，YU Junjian，LI Guo，et al. Experimental investigation on the mechanical properties of sandstone with different numbers of fractures before and after grouting[J]. Chinese Journal of Rock Mechanics and Engineering，2025，44(7)：1 767–1 781.(in Chinese))
[20] LAWANKAR S，KUMAR S，PANDIT B，et al. Dynamic behaviour of un-grouted and grouted jointed samples of a brittle rock in Split Hopkinson Pressure Bar tests：insights from experiments and DEM modelling[J]. Engineering Geology，2025，351：108033.
[21] 黄润秋. 岩石高边坡发育的动力过程及其稳定性控制[J]. 岩石力学与工程学报，2008，27(8)：1 525–1 544.(HUANG Runqiu. Geodynamical process and stability control of high rock slope development[J]. Chinese Journal of Rock Mechanics and Engineering，2008，27(8)：1 525–1 544.(in Chinese))
[22] 中华人民共和国行业标准编写组. T/CSRME 001—2019 岩石动力特性试验规程[S]. 北京：中国标准出版社，2019.(The Professional Standards Compilation Group of People?s Republic of China. T/CSRME 001—2019 Test specification for dynamic properties of rocks[S]. Beijing：China Standards Press，2019.(in Chinese))
[23] 李 贺. 岩石断裂力学[M]. 重庆：重庆大学出版社，1988：66–84.(LI He. Rcok fracture mechanics[M]. Chongqing：Chongqing University Press，1988：66–84.(in Chinese))
[24] 范星宇，刘海明，王希辉，等. 基于PFC的单节理岩石裂缝演化数值模拟[J]. 清华大学学报：自然科学版，2024，64(7)：1 238–1 251. (FAN Xingyu，LIU Haiming，WANG Xihui，et al. Numerical simulation of single-joint rock fracture evolution based on PFC[J]. Journal of Tinghua University：Science and Technology，2024，64(7)：1 238–1 251.(in Chinese))
[25] 宫凤强，李夕兵，刘希灵. 三维动静组合加载下岩石力学特性试验初探[J]. 岩石力学与工程学报，2011，30(6)：1 179–1 190.(GONG Fengqiang，LI Xibin，LIU Xiling. Preliminary experimental study of characteristics of rock subjected to 3D coupled static and dynamic loads[J]. Chinese Journal of Rock Mechanics and Engineering，2011，30(6)：1 179–1 190.(in Chinese))
[26] LI X B，GONG F Q，ZHOU Z L，et al. Several key problems in SHPB experiments of rock-based materials[C]// Proceedings of the 6th National Conference on Experimental Technology in Explosive Mechanics. [S. l]：[s. n.]，2010：6–19.
[27] 李 部，黄润秋，吴礼舟. 类岩石脆性材料非闭合裂纹的Ⅰ–Ⅱ压剪复合型断裂准则研究[J]. 岩石力学与工程学报，2017，39(4)：662–668.(LI Bu，HUANG Runqiu，WU Lizhou. Compression-shear fracture criteria for mixed mode I-II of open crack of rock-like brittle materials[J]. Chinese Journal of Rock Mechanics and Engineering，2017，39(4)：662–668.(in Chinese))
[28] 村上敬宜. 应力强度因子手册[M]. 鞠泽啸，郎福臣，译. 北京：中国铁道出版社，1990：200.(MURAKAMI T. Handbook of stress intensity factors[M]. Translated by JU Zexiao，LANG Fuchen. Beijing：China Railway Publishing House，1990：200.(in Chinese))
[29] 寇苗苗. 卸荷渗流耦合作用下裂隙岩体破坏机制研究[博士学位论文][D]. 重庆：重庆大学，2021.(KOU Miaomiao. Study on the failure mechanism of fractured rock masses under the coupled hydro-mechanical loading and unloading conditions[Ph. D. Thesis][D]. Chongqing：Chongqing University，2021.(in Chinese))
[30] LEMAITRE J. A course on damage mechanics[M]. Berlin，Heidelberg：Springer，1992：13–14.
[31] 李世愚，和泰名，尹祥础. 岩石断裂力学导论[M]. 合肥：中国科学技术大学出版社，2010：89–98.(LI Shiyu，HE Taiming，YIN Xiangchu. Introduction of rock fracture mechanics[M]. Hefei：University of Science and Technology of China Press，2010：89–98.(in Chinese))
[32] 楼志文. 损伤力学基础[M]. 西安：西安交通大学出版社，1991：14–18.(LOU Zhiwen. Fundamentals of damage mechanics[M]. Xi?an：Xi?an Jiaotong University Press，1991：14–18.(in Chinese))
[33] 刘小明，李焯芬. 脆性岩石损伤力学分析与岩爆损伤能量指数[J]. 岩石力学与工程学报，1997，16(2)：140–147.(LIU Xiaoming，LI Zhuofen. Damage mechanics analysis for brittle rock and rockburst energy index[J]. Chinese Journal of Rock Mechanics and Engineering，1997，16(2)：140–147.(in Chinese))
[34] TAYLOR L M，CHEN E P，KUSAMAUL J S. Microcrack-induced damage accumulation in brittle rock under dynamic loading[J]. Computer Methods in Applied Mechanics and Engineering，1986，55(3)：301–320.
[35] GRADY D L，KIPP M E. The micro-mechanics of impact fracture of rock[J]. International Journal of Rock Mechanics and Mining Sciences and Geomechanics Abstracts，1979，16(5)：293–302.
2026, Vol. 45 
