摘要
运用MTS 815岩石力学试验系统和PCI-2全数字声发射监测系统对具有突出倾向煤体制备的型煤试件单轴压缩和循环加载过程中的AE特征进行了试验研究,利用扫描电镜和数值模拟软件分析了声发射事件的来源.结果表明:单轴压缩过程中,随着煤样变形的增加,AE各参数呈上升趋势,在屈服阶段的后期出现最大振幅和最密集AE事件区,预示试件将发生破坏;AE事件累计曲线和振幅变化曲线与单轴压缩应力应变曲线相似,可在现场用以判定煤体失稳与破坏;随循环载荷作用次数的增加,AE事件及其能量呈现递减趋势;在卸载阶段无AE事件出现.四种微结构变化是煤样产生声发射事件的源.
The characteristics of acoustic emission are studied with outburst-hazardous coal under uniaxial compression and cyclic loading by MTS 815 rock mechanical test system and PCI-2 based AE system,and the source of AE is analyzed by SEM and numerical simulation software.The results show that the AE of coal samples can be detected through the whole process of uniaxial compression,and the parameters of AE has a rising trend as the deformation of coal samples increases,maximum amplitude and the most intensive area of AE events appeared in the late yield step,which shows the sample reaches failure soon;the curves of cumulative AE events and amplitude change is similar to the curve of stress-strain under uniaxial compression,which can be used to forecast the failure of coal in field;AE events appeared in regularity as the times of cyclic loading,the value and energy of AE reaches in the first loading stage;different times of AE events appeared in every loading process of cyclic loading and has a decreasing trend,but no AE event in the unloading process.The change of four kinds of Microstructure is the source of AE.
出处
《采矿与安全工程学报》
EI
北大核心
2010年第4期543-547,共5页
Journal of Mining & Safety Engineering
基金
国家自然科学基金重点项目(50834005)
国家自然科学基金项目(50974123)
煤炭资源与安全开采国家重点实验室开放基金项目(SKLCRSM09KFB09)
中央高校基本科研业务费资助项目(2009QZ03)
关键词
突出煤体
声发射
单轴压缩
循环载荷
声发射源
outburst-hazardous coal
acoustic emission
uniaxial compression
cyclic loading
acoustic emission source
