卸载速率对卸载诱发注浆加固节理岩体滑移行为影响的试验研究  

An experimental study on the effect of unloading rate on the slip behavior of unloading-induced grouting-reinforced jointed rock

作　　者：卢英瑞 冯现大[1] 刘日成[2] 李树忱 胡明慧 董峰吉 LU Ying-rui;FENG Xian-da;LIU Ri-cheng;LI Shu-chen;HU Ming-hui;DONG Feng-ji(School of Civil Engineering and Architecture,University of Jinan,Jinan,Shandong 250000,China;State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering,China University of Mining and Technology,Xuzhou,Jiangsu 221116,China)

机构地区：[1]济南大学土木建筑学院,山东济南250000 [2]中国矿业大学深地工程智能建造与健康运维全国重点实验室,江苏徐州221116

出　　处：《岩土力学》2024年第8期2397-2410,共14页Rock and Soil Mechanics

基　　金：国家自然科学基金(No.52379102,No.52379113)。

摘　　要：为研究卸载速率对水泥注浆加固节理花岗岩卸载诱发滑移行为的影响,利用TATW-2000岩石三轴试验系统对接近临界应力状态下的注浆加固节理花岗岩进行了恒轴压分级卸围压的诱发滑移试验,卸载速率分别为0.1、0.5、1、5、10 MPa/min。研究表明:(1)在剪切滑移过程中,岩-浆黏结界面会相互磨损,花岗岩会在水泥断面表面留下大量微划痕。随着卸载速率升高,节理粗糙度系数(joint roughness coefficient,JRC)值分别为17.52、16.25、15.65、12.82、10.72,这表明卸载速率越大,水泥断面表面的微划痕越小。(2)各围压卸载期内的平均剪切滑移速率随卸载速率变化关系符合幂函数关系,平均剪切滑移速率随卸载速率的升高而升高,但升高速率逐渐减小。在应力-应变滞后效应的影响下,各围压保持期内的平均剪切滑移速率也随卸载速率的增加而增加。卸载速率为0.5、1、5、10 MPa/min时,围压保持期的平均剪切滑移速率远小于围压卸载期的平均剪切滑移速率;卸载速率为0.1 MPa/min时,围压卸载期和围压保持期的平均剪切滑移速率相对差距较小。(3)动态滑移的平均剪切滑移速率比蠕变滑移的平均剪切滑移速率高一个数量级。蠕变滑移和动态滑移的平均剪切滑移速率随卸载速率的升高而升高,持续时间随卸载速率的升高而减小。(4)卸载速率小于1 MPa/min时,试样发生失稳滑移时对应的围压与卸载速率呈正相关,卸载速率大于1 MPa/min时呈负相关。To investigate the effect of unloading rate on the unloading-induced slip behavior of cement grouting-reinforced jointed granite,a constant axial pressure graded unloading perimeter pressure induced slip test was carried out on the grouting reinforced jointed granite in the state of close to critical stress by using the TATW-2000 rock triaxial test system,The unloading rates are 0.1,0.5,1,5,and 10 MPa/min respectively.The study showed that:(1)During the shear slip process,the rock-slurry bond interface undergoes abrasion,leaving numerous micro-scratches on the cement section surface of the granite.As the unloading rate increases,the JRC values are 17.52,16.25,15.65,12.82,and 10.72,which indicates that the larger the unloading rate is,the smaller the micro-scratches on the surface of the cement section are.(2)The relationship between the average shear slip rate and the unloading rate during each perimeter pressure unloading period conforms to a power function relationship,and the average shear slip rate increases with the unloading rate,but the rate of increase gradually decreases.Under the influence of stress-strain hysteresis effect,the average shear slip rate in each perimeter pressure holding period also increases with the unloading rate.At unloading rates of 0.5,1,5,and 10 MPa/min,the average shear slip rates during the perimeter pressure holding period are much smaller than those during the perimeter pressure unloading period,and the relative difference between the average shear slip rates during the perimeter pressure unloading period and that during the perimeter pressure holding period is smaller at an unloading rate of 0.1 MPa/min.(3)The average shear slip rate of dynamic slip is one order of magnitude higher than the average shear slip rate of creep slip.The average shear slip rates for creep slip and dynamic slip increase with increasing unloading rate,while the duration decreases with increasing unloading rate.(4)When the unloading rate is less than 1 MPa/min,the peripheral pressure corresponding to t

关 键 词：岩石力学 卸载诱发滑移 卸载速率 节理岩体 剪切滑移速率 

分 类 号：TU452[建筑科学—岩土工程]