低频重复扰动下预加应力结构面变形破坏特性试验研究  

Deformation and failure characteristics of pre-stressed joints under repeated low frequency disturbances

作　　者：杨嘉楠 范鹏贤 王明洋 YANG Jianan;FAN Pengxian;WANG Mingyang(State Key Laboratory of Disaster Prevention and Mitigation of Explosion and Impact,Army Engineering University of PLA,Nanjing,Jiangsu 210007,China)

机构地区：[1]陆军工程大学爆炸冲击防灾减灾国家重点实验室,江苏南京210007

出　　处：《岩石力学与工程学报》2023年第7期1720-1730,共11页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(51979280)。

摘　　要：深部围岩结构面常处于较高的应力作用下,在爆炸冲击引起的扰动作用下极易诱发失稳。为揭示结构面在强度极限邻域内的扰动剪切失稳特性,采用对称剪切试件对不同起伏角的规则齿形结构面开展不同初始应力、扰动峰值、扰动频率条件下的扰动剪切试验,分析结构面扰动失稳的变形规律和能量演化特征。试验结果表明:同类型结构面的扰动失稳位移与准静载条件下的失稳位移相差不大,不可逆位移累积曲线呈现“三阶段”的特征;初始应力状态控制着结构面的失稳位移量值;高初始应力、高扰动幅值、低扰动频率条件下失稳更容易发生;扰动变形过程中加载能量与卸载可恢复能量呈现“双向背离”特征。When disturbed by blast impacts,the high-stress deep surrounding rock joints tend to induce instability failure.To investigate the disturbance shear instability characteristics of rock joints in the neighborhood of strength limit,a series of disturbance shear tests under different initial stresses,disturbance peaks and disturbance frequencies were carried out on symmetrical regular dentate rock joints.The deformation and energy evolution laws of rock joints in the process of disturbance instability were also analyzed.Test results show that the disturbance instability displacement of same rock joints is close to that under quasi-static loading and the cumulative curve of irreversible deformation presents in three stages.Instability displacement of rock joints is controlled by the initial stress state,and the instability is more likely to occur under high initial stress,high disturbance peak and low disturbance frequency.The loading energy and unloading recoverable energy show the“two-way deviation”feature during the deformation process.

关 键 词：岩石力学 预加应力结构面 低频扰动 强度极限邻域 不可逆位移 能量演化 

分 类 号：TU45[建筑科学—岩土工程]