裂隙岩体化学注浆加固后力学性质及表征单元体的试验研究  

Experimental investigation on mechanical properties and representative elementary volume for chemically grouted fractured rock masses

作　　者：胡巍[1] 隋旺华[1] 王档良[1] 马路兴[1] 

机构地区：[1]中国矿业大学深部岩土力学与地下工程国家重点实验室资源与地球科学学院,江苏徐州221008

出　　处：《中国科技论文》2013年第5期408-412,共5页China Sciencepaper

基　　金：国家自然科学基金资助项目(41072237);高等学校博士学科点专项科研基金资助项目(20100095110015)

摘　　要：通过室内单轴压缩及剪切试验,分析了裂隙岩体注浆加固后不同试块的强度变形特征,并对注浆加固前后裂隙岩体的表征单元体(REV)进行了数值模拟研究。单轴压缩时,试样中注浆裂隙倾角不同,岩体失稳破坏呈柱状劈裂破坏、滑移-劈裂破坏及滑移破坏;随着注浆裂隙倾角α从0°增大到90°,裂隙岩体试样的单轴压缩强度呈先减小后增大的变化趋势;相比于未注浆裂隙试样,注浆有效提升了试样的单轴抗压能力,且当裂隙倾角0°<α<45°时,改善效果最为明显。通过剪切试验可以发现,岩体试样的剪切强度随裂隙与剪切面夹角β的减小而减小,且裂隙密度越大,试样强度越小。相对于注浆前,试样剪切强度能够得到一定提高,但夹角β较大时,提升效果不明显。注浆加固前后,该工程岩体REV尺寸分别约为5m和4m,注浆后裂隙岩体的REV相对变小,且REV的等效抗压强度及弹性模量与未注浆裂隙岩体相比均有一定程度的提高。研究结果表明,注浆作用改善了裂隙岩体的完整性,无论对室内试样还是实际工程岩体,都在一定程度提高了岩体的物理力学性质。This paper presents an experimental investigation on the strength and deformation characteristics of chemically grouted fractured rock through uniaxial compression and shearing test in laboratory and a numerical simulation study of the representative elementary volume of fractured rock before and after grouting. In the experiments, the specimen with different dips of fracture has three failure forms, which are columnar cleavage failure, sliding-splitting failure and sliding failure. With the increase of dip angle from 0° to 90°, the specimen＇s uniaxial compression strength decreases and then increases. The modulus of elasticity is affected by fracture width significantly. Wile the increase of dip angle from 0°to 45°, It is found through the shearing test that shearing strength of rock masses is related to the angle between shear surface and fracture surface and the density of the fracture network. The length of the representative dementary volume is 5 m and 4 m before and after grouting reinforcement, respectively. After grouting reinforcement, the fractured rock＇s representative elementary volume is decreased to some extent, and the equivalent compression strength and modulus of representative elementary volume are raised. The results indicate that the completeness and quality of fractured rock masses after grouting reinforcement have been improved to varying degrees.

关 键 词：注浆 裂隙岩体 单轴压缩试验 剪切试验 表征单元体 

分 类 号：TU452[建筑科学—岩土工程]