单轴压缩条件下冲击煤岩声发射特性实验研究

为了更深入地了解具有冲击倾向性煤体声发射特性,利用RMT150B试验机对冲击煤体在单轴压缩条件下全过程声发射特性进行研究,得出煤岩体破坏时应力、声发射特性参数之间随时间的变化曲线,并将整个过程分为5个阶段。研究发现声发射参数在试样屈服阶段出现了"平静期",标志煤样破坏前兆。通过比较不同弹性模量试样的声发射特性,发现随着弹性模量的增加,声发射特性的平均水平越高。煤岩在加、卸载时,当加载至弹性阶段时卸载,煤样在压密阶段的声发射信号比相对应的卸载阶段明显要强,而在弹性阶段声发射基本相同。当加载至屈服阶段时卸载,声发射在整个加载阶段都要比卸载时强,且越接近临界载荷卸载越明显。

Experimental Research on Acoustic Emissions Characteristic of Coal and Rock with Bursting Liability under Uniaxial Compression

In order to understand acoustic emissions characteristic of coal and rock with bursting liability more deeply,RMT150B tester applied to researching acoustic emissions characteristic of coal with bursting liability under uniaxial compression,the paper obtained variation curve of stress and acoustic emissions parameter with time when coal failed.The whole procedure was divided into 5 phrases.Results showed that acoustic emissions parameter was stable at yield phrase which indicated portent of coal sample.With...