自然和饱水煤样受载破坏声发射特征实验研究  

Experimental Study on AE Characteristics of Natural and Water-saturated Coal in Process of Deformation and Fracture

作　　者：王笑然[1] 刘晓斐[1] 沈荣喜[1] 邓晓谦[1] 

机构地区：[1]中国矿业大学安全工程学院,江苏徐州221116

出　　处：《煤矿安全》2016年第1期28-32,共5页Safety in Coal Mines

基　　金：中国矿业大学第七批优秀创新团队建设资助项目(2014ZY001);教育部科学技术研究资助项目(113031A);"十二五"国家科技支撑计划资助项目(2012BAK09B01);国家大学生创新性实验计划资助项目(201310290065)

摘　　要：开展了单轴压缩自然和饱水煤样受载破坏实验,测试了煤样在整个加载过程中声发射信号脉冲、能量及主频等各参数的变化规律,对比分析了这2种煤样破坏声发射各参数随加载应力变化的差异性,总结了煤样失稳过程中声发射信号的前兆特征。结果表明:在压密阶段,2种煤样脉冲数和能量值较小,频带范围较宽,主频不突出;在线弹性阶段,自然煤样声发射脉冲数、能量值及主频波动上升,而饱水煤样在该阶段中后期声发射现象才开始明显出现;随着加载的进行,2种煤样声发射都出现了平静期,饱水煤样平静期出现较晚,持续时间也较短;煤样主频逐渐向低频移动,主频振幅却呈现出快速增高后下降趋势。In this paper, we use the experimental system to test the AE signals of natural and water - saturated coal samples during the process of deformation and fracture under uniaxial compression; their characteristics including AE signals pulse, energy and dominant frequency in the whole loading stages were analyzed. In addition, we summarized the precursory characteristics of AE signals in the process of coal deformation and fracture. The results suggest that the pulse and energy of AE signals of natural and water - saturated coal samples are both less in compression phase ; the frequency bands of both are wider, the dominant frequency is not obvious and the amplitude of dominant frequency is less ; in elastic stage, the pulse, energy and dominant fi＇equency of AE signals of natural coal show a fluctuant rise, while not until middle and later elastic stage make the AE signals of water - saturated coal begin to appear clearly, and then the dominant frequency of AE also has a rising tendency; in the elastic - plastic stage, the AE signals pulse and energy of both have the relatively quiet period, however, the quiet period of water - saturated coal appears comparatively late and has a shorter dura- tion, in this stage, the dominant frequency of AE signals gradually moves to low frequency, but the amplitude of dominant frequency sharply increases and then decreases.

关 键 词：自然煤样 饱水煤样 加载过程 声发射特征 前兆信息 单轴压缩 

分 类 号：TD712[矿业工程—矿井通风与安全]