循环动载边界下三维粗糙节理面剪切力学响应研究  

Study on shear mechanical responses of three-dimensional rough joint surfaces under cyclic dynamic load boundary conditions

作　　者：尹乾[1,2,3] 何满潮 靖洪文[1] 王琦[2] 祁生文[3] 吴疆宇[1] 孟波 张强[1] 朱淳[2] 吴赛赛 YIN Qian;HE Manchao;JING Hongwen;WANG Qi;QI Shengwen;WU Jiangyu;MENG Bo;ZHANG Qiang;ZHU Chun;WU Saisai(State Key Laboratory for Geomechanics and Deep Underground Engineering,China University of Mining and Technology,Xuzhou,Jiangsu 221116,China;State Key Laboratory for Geomechanics and Deep Underground Engineering,China University of Mining and Technology(Beijing),Beijing 100083,China;Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China)

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,江苏徐州221116 [2]中国矿业大学(北京)深部岩土力学与地下工程国家重点实验室,北京100083 [3]中国科学院地质与地球物理研究所,北京100029

出　　处：《岩石力学与工程学报》2024年第5期1176-1189,共14页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金项目(52174092,51904290);江苏省优秀青年基金项目(BK20220157)。

摘　　要：开展正弦波式循环法向动载–循环剪切位移叠加作用下三维粗糙节理面剪切试验,探讨初始法向静载(Fs)、法向动载振幅(Fa)、法向动载频率(fv)及循环剪切次数(N)对节理面剪切特性的影响。随着Fs与Fa的增加,节理面法向荷载变化范围逐渐增大,一个剪切位移周期内剪切荷载呈现波动增加→波动减小→波动增加趋势;稳定状态下峰值剪切荷载随着Fs与Fa的增加分别增大4.90倍与65.12%,节理面抗剪能力逐渐增强,而随着fv的增加,节理表面损伤渐进累积导致峰值剪切荷载逐渐减小,且出现的时刻逐渐前移,稳定状态峰值剪切荷载减小17.49%。一个剪切位移周期内节理面法向位移呈现波动增加→波动减小→二次增加→二次减小的趋势,当节理面远离初始位置剪切时,凸起体持续“爬坡效应”导致法向位移逐渐增大;节理面法向位移–法向荷载呈现明显负相关,且最大法向位移滞后于最大剪切位移1/4法向荷载周期;随着N的增加,节理面持续磨损劣化导致最大法向位移呈指数函数减小趋势;最大法向位移随着Fs,Fa及fv的增加分别呈现逐渐减小、逐渐增加及先增后减的特征。剪切后节理表面粗糙度系数随着Fs,Fa与fv的增加,呈现的变化规律分别为减小了57.79%,43.26%以及以1 Hz为拐点先增加后减小的趋势。Shear tests of three-dimensional rough joint surfaces were conducted under superimposed actions of sinusoidal cyclic normal dynamic loads and sinusoidal cyclic shear displacements.The effects of initial normal static load(Fs),dynamic normal load amplitude(Fa),dynamic normal load frequency(v f)and the number of shear cycles(N)on the shear properties were explored.With an increasing of Fs or Fa,the variation range of the normal load for the joint surfaces gradually increases.Within a shear displacement cycle,the shear load experiences a variation of fluctuating increase→fluctuating decrease→fluctuating increase.The peak shear load in stable states increases by 4.90 times and 65.12%,respectively,with an increasing of Fs and Fa,implying a gradually enhanced shear resistance capacity.However,as v f increases,the progressive accumulation of damage on the joint surfaces results in a gradual reduction in the peak shear load,and the moment when the peak shear load occurs gradually moves forward.The peak shear load in stable states decreases by 17.49%.Within a shear displacement cycle,the normal displacement of joint surfaces shows a variation trend of fluctuating increase→fluctuating decrease→secondary increase→secondary decrease.When the joint surface shears away from the initial position,the continuous“climbing effects”of the surface asperities lead to a gradual increase in the normal displacement.A significant negative correlation between the normal displacement and normal load for the joint surfaces is recognized,and the maximum normal displacement lags behind the maximum shear displacement by a quarter of a normal load period.As N increases,the continuous wear and deterioration of the joint surfaces lead to an exponential decrease in the maximum normal displacement.The maximum normal displacement exhibits change characteristics of gradually decreasing with Fs,gradually increasing with Fa,and initially increasing and then decreasing with v f,respectively.The surface roughness coefficients of joints after

关 键 词：岩石力学 粗糙节理面 循环剪切 法向动载 法向位移 表面磨损 

分 类 号：TU45[建筑科学—岩土工程]