摘要
为了研究等离子冲击波作用下岩石的破裂行为,开展了不同放电间距下的高压脉冲击穿红砂岩试验。利用超高速相机观测了红砂岩试件的裂纹扩展过程,讨论了放电间距对等离子冲击波作用下红砂岩试样表面裂纹密度的影响。随后,利用数值模拟软件LS-DYNA建立与实验条件一致的有限元模型,对比了模拟和实验结果,再现了试验过程。结果表明:等离子冲击波作用下,垂直放电通道方向的两个表面上的破坏主要是径向裂纹;平行放电通道的四个侧面则是横向裂纹占主导。随着放电间距的增大,试件表面的裂纹密度逐渐增大。依据数值模拟结果对试件内部的破裂过程及应力波的衰减进行了分析。结果表明:随着放电间距的增加,等离子冲击波在红砂岩试样内部形成的有效应力呈现出指数型衰减,在自由面附近有效应力峰值趋于稳定。
In order to investigate the fracturing behavior of rocks under the influence of plasma shock waves,high-voltage pulsed breakdown experiments on red sandstone were conducted at various discharge distances.The crack propagation process of red sandstone specimens was observed by an ultra-high-speed camera,and the influence of discharge distance on the surface crack density of red sandstone under plasma shock wave was discussed.Subsequently,a finite element model,in line with the experimental conditions,was developed using the numerical simulation software LS-DYNA,the simulation and experimental results were compared,and the experimental process was reproduced.The results indicated that under the action of the plasma shock wave,the damage on the two surfaces perpendicular to the discharge channel is mainly radial cracks,while the damage on the four sides parallel to the discharge channel is mainly transverse cracks.As the discharge distance increased,the crack density on the surface of the specimens gradually increased.The numerical simulation results were used to analyze the internal fracturing process of the specimens and the attenuation of stress waves.It was found that as the discharge distance increased,the effective stress generated within the red sandstone samples by the plasma shock waves exhibited an exponential decay,with the peak effective stress near the free surface tending towards stability.
作者
李欣冉
饶珂嘉
苏贺
侯雨函
冯茂根
彭建宇
张凤鹏
LI Xinran;RAO Kejia;SU He;HOU Yuhan;FENG Maogen;PENG Jianyu;ZHANG Fengpeng(Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines,Northeastern University,Shenyang 110819,China;College of Information Science and Engineering,Northeastern University,Shenyang 110819,China)
出处
《有色金属（矿山部分）》
2024年第3期170-177,185,共9页
NONFERROUS METALS(Mining Section)
基金
国家自然科学基金资助项目(52274114)
大学生创新创业计划项目(231097)。
关键词
高压电脉冲
放电间距
裂纹扩展
裂纹密度
应力波
high voltage electric pulse
discharge distance
crack propagation
crack density
stress wave
作者简介
李欣冉(2003—),女,采矿工程专业,研究方向为高压电脉冲放电破岩。E-mail:20212567@stu.neu.edu.cn;通信作者:彭建宇(1987—),男,副教授,博士研究生导师,研究方向为深部工程高效爆破理论与技术及高压脉冲放电破岩新技术。E-mail:pjy069@163.com。
