摘要
为了探究预制裂纹对水中高压电脉冲致裂煤岩体的影响,提高矿区煤岩层渗透性,分别对包含和不含预制裂纹煤岩体相似试样进行了高压电脉冲致裂试验;在此基础上,运用PFC数值模拟软件,建立不同峰值压力下的包含和不含预制裂纹煤岩体模型进行致裂模拟。试验和模拟结果均表明:预制裂纹对高压脉冲放电致裂煤岩体有一定的促进作用;预制裂纹对裂纹的扩展具有一定的导向作用,但裂纹最终沿平行于最大主应力的方向进行扩展;随着峰值压力越高,预制裂纹旁形成的裂纹网络发育得越丰满、沿着预制裂纹的端头向外延伸的裂纹长度减小、与不含预制裂纹的力链断裂数目差值也在减小。
In order to explore the influence of prefabricated cracks on coal rock mass induced by high voltage electric pulse in water,and improve the permeability of coal and rock strata in the mining area,the high voltage pulse cracking tests were carried out on similar samples of coal and rock mass with and without prefabricated cracks.On this basis,PFC numerical simulation software was used to build coal and rock mass models with and without prefabricated cracks under different peak pressures for fracture simulation.The experimental and simulation results show that the prefabricated cracks have a certain promoting effect on the fractured coal and rock mass caused by high pressure pulse discharge.The prefabricated crack has a certain guiding effect on the crack propagation,but the crack propagates along the direction parallel to the maximum principal stress.With the increase of the peak pressure,the crack network formed next to the prefabricated crack develops more fully,the crack length extending outward along the end of the prefabricated crack decreases,and the difference between the number of force chain fractures and those without the prefabricated crack also decreases.
作者
李春明
赵胤翔
赵金昌
杨双锁
马忠忠
LI Chunming;ZHAO Yinxiang;ZHAO Jinchang;YANG Shuangsuo;MA Zhongzhong(College of Mining Engineering,Taiyuan University of Technology,Taiyuan 030000,China)
出处
《煤矿安全》
CAS
北大核心
2021年第7期27-32,共6页
Safety in Coal Mines
基金
山西省自然科学基金资助项目(201701D22111223,201801D221339)。
关键词
煤岩层增透
水中脉冲放电
液电现象
预制裂纹
裂纹扩展
permeability improvement of coal strata
pulse discharge in water
hydroelectricity phenomenon
prefabricated cracks
crack propagation
