赵固二_(1)煤样冲击倾向性与声发射特征的试验研究  

Experimental study on impact proneness and acoustic emission characteristics of coal samples from Zhaogu No.2_(1) mine

作　　者：冯志杰[1,4] 苏发强 苏承东[2] 郭健卿 FENG Zhijie;SU Faqiang;SU Chengdong;GUO Jianqing(Institute of Information Engineering,Chinese Academy of Sciences,Beijing 100093,China;School of Energy Science and Engineering,Henan Polytechnic University,Jiaozuo,Henan 454003,China;State Key Laboratory for Geomechanics&Deep Underground Engineering,Xuzhou,Jiangsu 221116,China;School of Cyber Security,University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院信息工程研究所,北京100093 [2]河南理工大学能源科学与工程学院,河南焦作454010 [3]深部岩土力学与地下工程国家重点实验室,江苏徐州221116 [4]中国科学院大学网络空间安全学院,北京100049

出　　处：《采矿与安全工程学报》2022年第1期25-35,共11页Journal of Mining & Safety Engineering

基　　金：深部岩土力学与地下工程国家重点实验室开放基金项目(SKLGDUEK2004);西部矿井开采及灾害防治教育部重点实验室开放基金项目(SKLCRKF1902);河南省矿产资源绿色高效开采与综合利用重点实验室开放基金项目(KCF201801)。

摘　　要：煤矿冲击地压是煤矿灾害之一,煤岩体冲击倾向性指数是煤岩体的自然属性,利用RMT-150B伺服试验机对赵固二_(1)煤样进行冲击倾向性指数测试,在加载过程同步进行声发射信号检测,分析煤样冲击倾向性指数、关联性及声发射特征。试验结果表明:在煤样受载变形破坏过程中始终伴随着声发射事件,当载荷接近煤样峰值强度时宏观裂隙逐步形成,声发射活动异常活跃,声发射幅值、计数和能量均达到最大值,且超前于峰值强度3~17 s,声发射计数和能量累计曲线出现突变现象,可以作为判定煤样临近破坏前兆信息,与峰值前相比峰值后的声发射幅值、计数、能量有所降低。煤样抗压强度与弹性模量、峰值前积蓄能量呈正相关性,与冲击能指数、动态破坏时间呈负相关,可以采用线性拟合来表征单轴抗压强度与弹性模量、峰值前积蓄能量的特征。煤样抗压强度越高、弹性模量越大,积蓄弹性能越高,发生冲击地压的危险强度也就越大。对于煤层进行弹性能指数鉴定时,采用声发射同步检测煤样损伤演化过程,依据声发射突变信号作为卸载点更有利确定样弹性能指数。赵固二_(1)煤样单轴抗压强度为53.0 MPa,弹性模量为4.21 GPa,冲击能量指数5.45,动态破坏时间为708 ms,弹性能指数为16.44,综合评定二_(1)煤为(Ⅲ类)强冲击类型煤层。Rockburst is a disaster in coal mine and burst tendency index is a natural attribute of coal and rock mass.The impact tendency index of Zhaogu No.2_(1) coal samples was tested with RMT-150 B servo testing machine,acoustic emission signal was detected synchronously during loading,and impact tendency index,correlation,and acoustic emission characteristics of coal samples were analyzed.The results have shown that 1)The process of coal sample deformation and failure is throughout accompanied by AE events.When the load is close to peak strength of coal samples,macro cracks gradually form,and AE activity is extremely active;the amplitude,count,and energy of acoustic emission reach maximum value,and are ahead of peak strength in 3-17 s;the sudden change of AE count and energy accumulation curve can be taken as precursor information to judge coal sample near failure.Compared with pre-peak value,AE amplitude,count,and energy after peak value decrease.2)The compressive strength of coal samples is positively correlated with elastic modulus and accumulated energy before value,and negatively correlated with impact energy index and dynamic failure time.Linear fitting can be used to signify characteristics of uniaxial compressive strength,elastic modulus,and accumulated energy before peak value.The higher the compressive strength and elastic modulus of coal samples,the higher the accumulated elastic energy and the greater the dangerous strength of rock burst will be.3)During identification of elastic energy index of coal seam,it is more advantageous to determine performance index of projectile by acoustic emission simultaneous detection of damage evolution process of coal samples.4)The uniaxial compressive strength of Zhaogu No.2_(1) coal samples is 53.0 MPa,the elastic modulus is 4.21 GPa,the impact energy index is 5.45,dynamic failure time is 708 ms,and the elastic energy index is 16.44.Therefore,Zhaogu No.2_(1) coal seam is classified as(ClassⅢ)strong shock type coal seam.

关 键 词：冲击地压 煤样 单轴压缩 冲击倾向性指数 声发射特征 

分 类 号：TD353[矿业工程—矿井建设]