砂质充填型节理剪切力学行为试验研究  

Experimental investigation on shear mechanical behaviour of joints with sandy fillings

作　　者：杨泰华[1] 黄友琦 刘滨[2] 康永水[2] 耿志 周秀斌 YANG Tai-hua;HUANG You-qi;LIU Bin;KANG Yong-shui;GENG Zhi;ZHOU Xiu-bin(School of Urban Construction,Wuhan University of Science and Technology,Wuhan,Hubei 430065,China;State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan,Hubei 430071,China)

机构地区：[1]武汉科技大学城市建设学院,湖北武汉430065 [2]中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室,湖北武汉430071

出　　处：《岩土力学》2024年第12期3645-3657,共13页Rock and Soil Mechanics

基　　金：国家自然科学基金面上项目(No.42277170,No.U22A20234)。

摘　　要：由于长期地质构造运动引起的挤压剪切作用,断层破碎带岩体通常充填有类砂质、类泥质等充填物,对岩体的剪切力学特性产生显著影响,并影响岩体的注浆胶结效果。以我国云南某穿越断层带的公路隧道为例,对从断层带采集的岩石和充填物制作成的岩石节理试件进行一系列直剪试验,在此基础上分析了砂质充填对岩石节理注浆前后剪切特性和剪切强度的影响规律。结果表明:(1)对于非注浆试件和注浆试件,砂质充填都会导致节理峰值抗剪强度降低,前者是砂质弱化了节理岩壁之间的接触,后者是砂质影响了水泥结石的强度以及填充层的厚度;(2)注浆能够明显提高砂质充填型岩石节理的抗剪强度,且节理的充填度越高,加固后抗剪强度对比加固前抗剪强度的提升幅度越大;(3)基于节理粗糙度系数-节理压缩强度强度(joint roughness coefficient-joint compression strength,JRC-JCS)准则建立了砂质充填岩石节理以及砂质充填的注浆岩石节理抗剪强度模型,两个模型的预测值与试验数据的吻合度较高。有助于进一步了解断层泥对裂隙岩体注浆胶结的影响。Due to the extrusion shear action caused by long-term tectonic movement,fault zones are usually filled with fault gouge,significantly affecting the mechanical behavior of the rock mass and influencing the cementation effect of grouting.This study investigates the compression-shear behavior of grouted and non-grouted rock joints with sandy fillings,based on a tunnel passing through a fault zone in Yunnan Province,China.A series of direct shear tests was conducted on grouted and non-grouted rock joint samples with varying degrees of filling.The test results show that:1)For both grouted and non-grouted specimens,sandy filling reduces the peak shear strength of joints.The former is because the sand weakens the contact between the joint walls,while the latter is because the sand affects the strength of cement stones and the thickness of the filled layer.2)Grouting significantly improves the shear strength of rock joints with sandy fillings.The higher the filling degree,the greater the increase in shear strength after reinforcement.3)Based on the joint roughness coefficient-joint compression strength(JRC-JCS)criterion,shear strength models for grouted and non-grouted rock joints with sandy fillings were established.The predicted values of these models were in good agreement with the test data.It is helpful to further understand the influence of fault gouge on grouting cementation of fractured rock mass.

关 键 词：断层 岩石节理 抗剪强度 砂质充填 注浆 

分 类 号：TU452[建筑科学—岩土工程]