循环载荷下煤裂隙演化试验研究  

Experimental study on crack evolution of coal under cyclic loading

作　　者：郭军杰 程晓阳[3,4] GUO Junjie;CHENG Xiaoyang(School of Safety Engineering,Henan Institute of Engineering,Zhengzhou Henan 451191,China;State and Local Joint Engineering Laboratory for Gas Drainage&Ground Control of Deep Mines,Henan Polytechnic University,Jiaozuo Henan 454000,China;State Key Laboratory of the Gas Disaster Detecting,Preventing and Emergency Controlling,Chongqing 400037,China;China Coal Technology Engineering Group Chongqing Research Institute,Chongqing 400037,China)

机构地区：[1]河南工程学院安全工程学院,河南郑州451191 [2]河南理工大学深井瓦斯抽采与围岩控制技术国家地方联合工程实验室,河南焦作454000 [3]瓦斯灾害监控与应急技术国家重点实验室,重庆400037 [4]中煤科工集团重庆研究院有限公司,重庆400037

出　　处：《中国安全生产科学技术》2018年第2期39-44,共6页Journal of Safety Science and Technology

基　　金：深井瓦斯抽采与围岩控制技术国家地方联合工程实验室开放基金项目(G201615);2018年度河南省高等学校重点科研项目(18A440009);国家安全生产监督管理总局资助项目(henan-014-2013AQ)

摘　　要：为了研究循环载荷下的煤体裂隙演化特征,在不同应力水平和不同频率条件下分别进行煤样破坏力学及声发射试验。结果表明:应力-应变曲线呈疏-密-疏的变化特征,对应的振铃数柱状图呈U型;上限应力点的应变值、累积能量、撞击计数均随循环次数增加而上升,曲线呈倒S型;煤裂隙演化经历了原始裂隙闭合、新生裂隙稳定发育和裂纹贯穿破坏等3个不同阶段;循环载荷的应力水平和加载频率对煤体疲劳寿命的影响具有差异性,对煤体裂隙演化和破坏模式均有明显影响。In order to study the crack evolution characteristics of coal under the cyclic loading,the mechanics and acoustic emission experiments of coal samples failure were carried out under different stress levels and different frequencies respectively.The results showed that the stress-strain curves showed the changing characteristics of sparse-dense-sparse,and the corresponding histograms of ringing count were the"U"type.The strain values of the upper limit stress points,the accumulated energy and the impact count were all rising with the increase of cycling times,and the curves were the reverse"S"type.The crack evolution of coal went through three different stages:the closure of the original crack,the stable development of the new crack and the penetrated failure of crack.The stress level and loading frequency of the cyclic loading had different effect on the fatigue life of coal,and had obvious effect on the crack evolution and failure mode of coal.

关 键 词：循环载荷 裂隙演化 声发射 破坏模式 煤层 

分 类 号：X936[环境科学与工程—安全科学] TD315[矿业工程—矿井建设]