摘要
注浆是裂隙岩体稳定性控制的主要技术之一,不同注浆材料对裂隙岩体的注浆加固效果存在较大差异。选取硫铝酸盐水泥(SAC)、普通硅酸盐水泥(OPC)和环氧树脂(EPR)3种注浆材料,对预制平行双裂隙类岩石试样进行充填,开展单轴压缩试验、声发射以及扫描电镜试验。结果表明:EPR填充对裂隙试样强度最大,OPC水泥次之,SAC水泥最小。试样破坏模式则受填充材料影响突出,EPR填充试样不受预制裂纹控制,而SAC和OPC填充试样则主要由于裂隙扩展贯通发生的拉剪混合破坏。扫描电镜结果表明上述差异主要受控于不同浆液类型的浆-岩胶结特征,SAC和OPC填充浆-岩界面为覆盖型,而EPR填充则为融合型。在上述试验结果基础上,采用颗粒流程序(PFC)建立表征不同胶结模式的数值模型,分析不同注浆填充材料加固机制。数值模拟结果表明,试样加载过程中拉剪微裂纹比例、微裂纹倾角分布以及颗粒位移方向均受填充材料影响。因此,对于不同注浆材料,其自身强度和胶结性能改变了浆-岩胶结模式,影响了裂隙充填试样的受力状态,进而造成加载过程中浆液和周围岩体颗粒运动和微破裂的差异,最终影响了宏观强度特性和破坏模式。
Grouting is one of the main technologies for controlling the stability of fractured rock masses,and different grouting materials have significant differences in their reinforcement effects on fractured rock masses.In this study,three grouting materials,sulfate-aluminate cement(SAC),ordinary Portland cement(OPC),and epoxy resin(EPR),were selected to fill pre-existing parallel double-cracks rock samples,and uniaxial compression tests、AE and SEM tests were conducted on these samples.The results showed that epoxy resin filling had the highest strength for the fissured samples,followed by OPC cement,and SAC cement had the lowest strength.The failure mode of the samples was significantly influenced by the filling material,with EPR-filled samples not being controlled by pre-existing cracks,while SAC and OPC-filled samples mainly exhibited a tensile-shear mixed failure caused by crack extension and breakthrough.Electron microscopy scans indicated that the differences were primarily due to the bonding characteristics between the different grout types and the rock.The interfaces of SAC and OPC filling were of the cover type,while EPR filling belonged to the fusion type.Based on these experimental results,a numerical model representing different bonding patterns was established using the Particle Flow Code(PFC),and the reinforcement mechanisms of different grouting materials were analyzed.The numerical simulation results showed that the proportion of tensile-shear microcracks,the distribution of microcrack inclination angles,and particle displacement vectors during the sample loading process were significantly influenced by the grouting material.Due to differences in the strength and bonding performance of the grout itself,the bonding pattern between the grout and the rock was altered,leading to changes in the movement of grout and rock particles and microcrack formation during the loading process,ultimately resulting in differences in macroscopic strength and failure modes.
作者
刘学伟
王赛
刘滨
刘泉声
姚文杰
贾闯
陈海啸
LIU Xuewei;WANG Sai;LIU Bin;LIU Quansheng;YAO Wenjie;JIA Chuang;CHEN Haixiao(State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan,Hubei 430071,China;Faculty of Engineering,China University of Geosciences(Wuhan),Wuhan,Hubei 430074,China;School of Civil Engineering,Wuhan University,Wuhan,Hubei 430072,China)
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2024年第3期623-638,共16页
Chinese Journal of Rock Mechanics and Engineering
基金
国家自然科学基金资助项目(U22A20234)
湖北省重点研发计划项目(2023BCB121)。
关键词
岩石力学
注浆材料
浆岩胶结
强度特征
数值模拟
破坏特征
rock mechanics
grouting materials
grout-rock bonding
strength property
numerical simulation
failure mechanism
