基于声发射信号特征的花岗岩岩爆破坏前兆信息研究  

Failure precursor of granite rockburst based on acoustic emission signal characteristics

作　　者：赵菲 孟世卓 刘冬桥[2] 黄志全 袁广祥 胡晨洋 王海玥 王洪建 ZHAO Fei;MENG Shizhuo;LIU Dongqiao;HUANG Zhiquan;YUAN Guangxiang;HU Chenyang;WANG Haiyue;WANG Hongjian(College of Geosciences and Engineering,North China University of Water Resources and Electric Power,Zhengzhou,Henan 450046,China;State Key Laboratory for Geomechanics and Deep Underground Engineering,China University of Mining and Technology(Beijing),Beijing 100083,China;School of Civil Engineering,Luoyang Institute of Science and Technology,Luoyang,Henan 471023,China;State Key Laboratory of Intelligent Coal Mining and Strata Control,Beijing 100013,China)

机构地区：[1]华北水利水电大学地球科学与工程学院,河南郑州450046 [2]中国矿业大学(北京)深部岩土力学与地下工程国家重点实验室,北京100083 [3]洛阳理工学院土木工程学院,河南洛阳471023 [4]煤炭智能开采与岩层控制全国重点实验室,北京100013

出　　处：《岩石力学与工程学报》2024年第11期2669-2686,共18页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(52074299);河南省重点研发专项资助(221111321500);煤炭智能开采与岩层控制全国重点实验室开放基金项目(SKLIS202421)。

摘　　要：为研究岩石岩爆失稳破坏前兆信息,利用花岗岩开展岩爆室内模拟声发射监测试验,获得花岗岩岩爆的破坏模式和强度特性,基于声发射参数和多重分形维计算,定量化分析花岗岩岩爆过程时序分形特性和裂缝演化特性。结果表明:花岗岩在真三轴加卸载条件下发生猛烈的岩爆破坏,破裂强度为其单轴抗压强度的0.76~1.04倍;岩爆发生前,声发射振铃计数呈现出密集爆发式增长而声发射b值则出现突然间的持续性骤降;基于声发射聚类算法进行RA-AF分布划分,发现剪切型裂缝占比经历了先增长后保持稳定或略微降低到再次显著增长的过程,而声发射多重分形维谱宽Δα在岩爆发生时刻会呈现突降,剪切型裂缝占比再次发生突变开始持续性增大以及Δα突降的转折点可以作为岩爆失稳破坏的前兆信息;对比声发射振铃计数、b值、RA-AF分布、多重分形获得的岩爆预警信息,其平均前兆响应系数分别为0.72%,2.18%,5.40%和3.97%。研究表明:由于考虑岩石内部裂缝扩展演化和损伤时序特性,基于剪切裂缝占比和多重分形维判别前兆点的响应时间更早,更能精细刻画声发射信号复杂性,揭示岩石破裂演化机制。研究成果为揭示岩爆发生机制以及灾害预警方法的建立提供参考。To explore the precursor of rock instability,rockburst tests were conducted on granite using acoustic emission(AE)monitoring system.The failure mode and strength characteristics of granite rockburst were obtained.Based on acoustic emission parameters and multi fractal dimension calculation,the temporal fractal characteristics and crack evolution characteristics of granite during rockburst process were quantitatively analyzed.The results show that granite experiences violent blasting destruction under true triaxial loading and unloading conditions.The rupture strength is 0.76-1.04 times of its uniaxial compressive strength.Before the rockburst,the AE ringing counts have an intensive and explosive growth while the AE b-value shows a sudden continuous decline;Based on AE cluster analysis of RA-AF distribution division,it is found that the proportion of shear type cracks increases at first and then becomes stable or has a little decrease until finally increases significantly.The multifractal spectral width Δα of AE exhibits a sudden decrease at the moment of rockburst occurrence.Hence,the second sudden increase in the proportion of shear type cracks and the sudden descent turning point of Δα can be served as precursors of rock instability.Compared the warning information of rockburst determined by AE ringing count,b-value,RA-AF distribution and multifractal dimension,the average precursor response coefficients are 0.72%,2.18%,5.40%and 3.97%,respectively.Since the evolution of internal cracks and time sequence property of damage in rock are taken into account,the response time for identifying precursor based on the proportion of shear cracks and multifractal dimension is earlier.They can more finely characterize the complexity of AE signals and reveal the mechanism of rock fracture evolution.The research results can provide reference for revealing the mechanism of rockburst occurrence and establishing disaster warning methods.

关 键 词：岩石力学 花岗岩 声发射 岩爆前兆 多重分形 

分 类 号：TU45[建筑科学—岩土工程]