岩石受载破坏裂纹扩展带电特性  

Charging characteristics of the crack propagation of rock under load

作　　者：宋晓艳[1] 李忠辉[2,3] 王恩元[3] 

机构地区：[1]中国矿业大学应用技术学院,江苏徐州221008 [2]中国矿业大学煤炭资源与安全开采国家重点实验室,江苏徐州221116 [3]中国矿业大学安全工程学院,江苏徐州221116

出　　处：《煤炭学报》2016年第8期1941-1945,共5页Journal of China Coal Society

基　　金：国家自然科学基金资助项目(51574231);教育部科学技术研究资助项目(113031A);中国矿业大学煤炭资源与安全开采国家重点实验室自主研究课题资助项目(SKLCRSM15X03)

摘　　要：为了研究岩石破裂过程电位分布特征及其产生机理,利用预制裂纹岩石试样实验测试了裂纹扩展途径的电位信号变化规律及裂纹两侧电位分布特征。结果表明,扩展裂纹的尖端和新形成的裂纹壁面是产生自由电荷的主要位置,在裂纹扩展路径上距离裂纹尖端近处产生的电位信号强度较高,距离远处产生的电位强度较低,裂纹扩展产生的最大电场强度为0.42 V/m;在裂纹扩展过程中裂纹两侧产生的电位信号极性呈正负对应变化,表明裂纹两侧产生的自由电荷性质相反,并交替变化;在裂纹扩展中新生裂纹两侧壁面电荷分离是自由电荷及电位的主导产生机制。裂纹壁面电荷的正负交替及裂纹扩展中两侧壁张翕运动引起的电场变化是煤岩产生电磁辐射的原因。In order to study the electric potential（ EP） distribution characteristics and generation mechanism during rock fracture,the change law and distribution characteristics of electric potential of the crack propagation path were tested with the pre-cracked rock samples. The results show that the tip of the crack and the newly formed crack surface are the dominant positions that the free charges are produced. The strength of electric potential is higher near the crack tip in the propagation path of the crack and lower far from the crack tip; the maximum electric field strength resulted from crack propagation is 0. 42 V / m. In the process of crack propagation,the EP signal polarity was positive and negative alternation,which showed that the property of free charges generated by cracks is opposite and change alternatively. The dominant mechanism of free charges and electric potential is the charge separation at two sides of the crack surface of the crack growth. The alternation of charges between positive and negative in the crack surface and the open and close of two crack surfaces during crack propagation resulting in the change of electric field are served as the reasons for electromagnetic radiation.

关 键 词：岩石 破坏 裂纹扩展 电位 带电特征 

分 类 号：TD311[矿业工程—矿井建设]