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| Micromechanical mechanisms of grouting reinforcement in rock joints and microstructure optimization of grout-rock bonding interfaces#br# |
| LU Yinlong，HE Mengqi，LI Wenshuai，WU Bingzhen，WANG Lianguo#br# |
(State Key Laboratory for Geomechanics and Deep Underground Engineering，China University of Mining and Technology，Xuzhou，Jiangsu 221116，China)
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Abstract The microstructure and its mechanical properties of grout-rock bonding interfaces fundamentally control the macroscopic deformation and failure behaviors of grouted rock joints. In this paper，a series of macroscopic direct shear tests，microscopic SEM scanning tests and nano-indentation tests were carried out on grouted jointed sandstone specimens. The macroscopic shear mechanical strength parameters，shear failure modes， microstructure characteristics of grout-rock bonding interfaces and micromechanical properties of the interfacial transition zone of the specimens were obtained，and the modification and optimization mechanisms of grout-rock bonding interfaces by using new grouting materials such as ultrafine cement and nano-SiO2 were discussed to overcome the microdefects in grout-rock bonding interfaces resulting from the ordinary Portland cement grout. The results show that the grout-rock interface at the microscale is characterized by high porosity and low strength interfacial transition zone with a certain thickness(about 10–30 μm). The interfacial transition zone is the weakest link in the composite structure of grouted rock joints，and there is a positive linear correlation between the microscopic indentation modulus and microscopic indentation hardness with the macroscopic cohesive force of grouted rock joints. The new grouting materials of ultrafine cement and nano-SiO2 can optimize the microstructure of grout-rock bonding interfaces，reduce the thickness of the interfacial transition zone，thereby improve the micromechanical properties of the interfacial transition zone and the macroscopic cohesive force of the grouted joints，but have little influence on the internal friction angle of the grouted joints.
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[1] 薛翊国，孔凡猛，杨为民，等. 川藏铁路沿线主要不良地质条件与工程地质问题[J]. 岩石力学与工程学报，2020，39(3)：445–468.(XUE Yiguo，KONG Fanmeng，YANG Weimin，et al. Main unfavorable geological conditions and engineering geological problems along Sichuan-Tibet railway[J]. Chinese Journal of Rock Mechanics and Engineering，2020，39(3)：445–468.(in Chinese))
[2] 李术才，刘 斌，孙怀凤，等. 隧道施工超前地质预报研究现状及发展趋势[J]. 岩石力学与工程学报，2014，33(6)：1 090–1 113. (LI Shucai，LIU Bin，SUN Huaifeng，et al. State of art and trends of advanced geological prediction in tunnel construction[J]. Chinese Journal of Rock Mechanics and Engineering，2014，33(6)：1 090–1 113.(in Chinese))
[3] LI S，LIU R，ZHANG Q，et al. Protection against water or mud inrush in tunnels by grouting：a review[J]. Journal of Rock Mechanics and Geotechnical Engineering，2016，8(5)：753–766.
[4] 孙晓明，陈 峰，梁广峰，等. 防膨胀软岩注浆材料试验及应用研究[J]. 岩石力学与工程学报，2017，36(2)：457–465.(SUN Xiaoming，CHEN Feng，LIANG Guangfeng，et al. Experimental and application research on grouting material for preventing swelling of soft rock[J]. Chinese Journal of Rock Mechanics and Engineering，2017，36(2)：457–465.(in Chinese))
[5] LU Y，WANG L，LI Z，et al. Experimental study on the shear behavior of regular sandstone joints filled with cement grout[J]. Rock Mechanics and Rock Engineering，2016，50(5)：1 321–1 336.
[6] MA H，LIU Q S. Prediction of the peak shear strength of sandstone and mudstone joints infilled with high water-cement ratio grouts[J]. Rock Mechanics and Rock Engineering，2017，50(8)：2 021–2 037.
[7] 孙辅庭，佘成学，万利台. 充填水泥浆岩石节理峰值剪切强度模型[J]. 岩石力学与工程学报，2014，33(12)：2 481–2 489. (SUN Futing，SHE Chengxue，WAN Litai. A peak shear strength model for cement filled rock joints[J]. Chinese Journal of Rock Mechanics and Engineering，2014，33(12)：2 481–2 489.(in Chinese))
[8] 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))
[9] 张庆松，李 鹏，张 霄，等. 隧道断层泥注浆加固机制模型试验研究[J]. 岩石力学与工程学报，2015，34(5)：924–934.(ZHANG Qingsong，LI Peng，ZHANG Xiao，et al. Model test of grouting strengthening mechanism for fault gouge of tunnel[J]. Chinese Journal of Rock Mechanics and Engineering，2015，34(5)：924–934.(in Chinese))
[10] 杨仁树，薛华俊，郭东明，等. 基于注浆试验的深井软岩CT分析[J]. 煤炭学报，2016，41(2)：345–351.(YANG Renshu，XUE Huajun，GUO Dongming，et al. Laboratory grouting experiment based CT analysis of grouted soft rocks in deep mines[J]. Journal of China Coal Society，2016，41(2)：345–351.(in Chinese))
[11] 韩立军，宗义江，韩贵雷，等. 岩石结构面注浆加固抗剪特性试验研究[J]. 岩土力学，2011，32(9)：2 570–2 576.(HAN Lijun，ZONG Yijiang，HAN Guilei，et al. Study of shear properties of rock structural plane by grouting reinforcement[J]. Rock and Soil Mechanics，2011，32(9)：2 570–2 576.(in Chinese))
[12] SALIMIAN M H，BAGHBANAN A，HASHEMOLHOSSEINI H，et al. Effect of grouting on shear behavior of rock joint[J]. International Journal of Rock Mechanics and Mining Sciences，2017，98：159–166.
[13] 郑 卓，李术才，刘人太，等. 注浆加固后岩体单一界面抗剪强度[J]. 岩石力学与工程学报，35(增2)：3 915–3 922.(ZHENG Zhuo，LI Shucai，LIU Rentai，et al. Shearing strength of single structural surface of grouted rock mass[J]. Chinese Journal of Rock Mechanics and Engineering，2016，35(Supp.2)：3 915–3 922.(in Chinese))
[14] 李 坤，佘成学. 灌浆节理压剪峰值抗剪强度数值试验研究[J]. 武汉大学学报：工学版，2012，45(5)：570–574.(LI Kun，SHE Chengxue. Numerical test study of peak shear strength of cement-grouted joint under compression shearing[J]. Engineering Journal of Wuhan University，2012，45(5)：570–574.(in Chinese))
[15] ZOLFAGHARI A，SOHRABI BIDAR A，MALEKI JAVAN M R，et al. Evaluation of rock mass improvement due to cement grouting by Q-system at Bakhtiary dam site[J]. International Journal of Rock Mechanics and Mining Sciences，2015，74(1)：38–44.
[16] 许宏发，耿汉生，刘伟东，等. 基于BQ的破碎岩体注浆加固强度增长理论[J]. 岩土工程学报，2014，36(6)：1 147–1 151.(XU Hongfa，GENG Hansheng，LIU Weidong，et al. Theory of strength increment of grouting-reinforced bodies for broken rock mass based on BQ[J]. Chinese Journal of Geotechnical Engineering，2014，36(6)：1 147–1 151.(in Chinese))
[17] 李召峰，李术才，刘人太，等. 富水破碎岩体注浆加固实验与机制研究[J]. 岩石力学与工程学报，2017，36(1)：198–207.(LI Zhaofeng，LI Shucai，LIU Rentai，et al. Grouting reinforcement experiment for water-rich broken rock mass[J]. Chinese Journal of Rock Mechanics and Engineering，2017，36(1)：198–207.(in Chinese))
[18] 刘长武，陆士良. 水泥注浆加固对工程岩体的作用与影响[J]. 中国矿业大学学报，2000，29(5)：454–458.(LIU Changwu，LU Shiliang. Reinforcement effect of cement grouting on engineering rock mass[J]. Journal of China University of Mining and Technology，2000，29(5)：454–458.(in Chinese))
[19] 刘泉声，周越识，卢超波，等. 含裂隙泥岩注浆前后力学特性试验研究[J]. 采矿与安全工程学报，2016，33(3)：509–514.(LIU Quansheng，ZHOU Yueshi，LU Chaobo，et al. Experimental study on mechanical properties of mudstone fracture before and after grouting[J]. Journal of Mining and Safety Engineering，2016，33(3)：509–514.(in Chinese))
[20] NěME?EK J. Creep effects in nanoindentation of hydrated phases of cement pastes[J]. Materials Characterization，2009，60(9)：1 028– 1 034.
[21] OLIVER W C，PHARR G M. An improved technique for determining hardness and elastic modulus using load and displacement sensing indentation experiments[J]. Journal of Materials Research，1992，7(6)：1 564–1 583.
[22] NASIR O，FALL M. Shear behaviour of cemented pastefill-rock interfaces[J]. Engineering Geology，2008，101(3/4)：146–153.
[23] CHEN J H，HAGAN P C，SAYDAM S. Shear behaviour of a cement grout tested in the direct shear test[J]. Construction and Building Materials，2018，166：271–279.
[24] KURODA M，WATANABE T，TERASHI N. Increase of bond strength at interfacial transition zone by the use of fly ash[J]. Cement and Concrete Research，2000，30(2)：253–258.
[25] IGARASHI S，BENTUR A，MINDESS S. Microhardness testing of cementitious materials[J]. Advanced Cement Based Materials，1996，4(2)：48–57.
[26] KOOHESTANI B，BELEM T，KOUBAA A，et al. Experimental investigation into the compressive strength development of cemented paste backfill containing Nano-silica[J]. Cement and Concrete Composites，2016，72：180–189.
[27] SHAIKH F U A，SHAFAEI Y，SARKER P K. Effect of nano and micro-silica on bond behaviour of steel and polypropylene fibres in high volume fly ash mortar[J]. Construction and Building Materials，2016，115：690–698.
[28] CHEN J J，KWAN A K H. Superfine cement for improving packing density，rheology and strength of cement paste[J]. Cement and Concrete Composites，2012，34(1)：1–10.
[29] 杨 洁，荣 冠，程 龙，等. 节理峰值抗剪强度试验研究[J]. 岩石力学与工程学报，2015，34(5)：884–894.(YANG Jie，RONG Guan，CHENG Long，et al. Experimental study of peak shear strength of rock joints[J]. Chinese Journal of Rock Mechanics and Engineering，2015，34(5)：884–894.(in Chinese))
[30] 沈明荣，张清照. 规则齿型结构面剪切特性的模型试验研究[J]. 岩石力学与工程学报，2010，29(4)：713–719.(SHEN Mingrong，ZHANG Qingzhao. Experimental study of shear deformation characteristics of rock mass discontinuities[J]. Chinese Journal of Rock Mechanics and Engineering，2010，29(4)：713–719.(in Chinese))
[31] 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))
[32] TANG C A. Numerical simulation of progressive rock failure and associated seismicity[J]. International Journal of Rock Mechanics and Mining Sciences，1997，34(2)：249–261.
[33] 申艳军，欣 魏，杨更社，等. 岩石–混凝土界面黏结强度冻融劣化模型及试验分析[J]. 岩石力学与工程学报，2020，39(3)：480–490.(SHEN Yanjun，WEI Xin，YANG Gengshe，et al. Freeze-thaw degradation model and experimental analysis of rock-concrete interface bond strength[J]. Chinese Journal of Rock Mechanics and Engineering，2020，39(3)：480–490.(in Chinese)) |
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2020, Vol. 39 
