不同加载条件下花岗岩声发射特征及其岩爆倾向性研究

Research into the acoustic emission characteristics of granite under different load conditions and rock burst proneness

试验现场取样并利用TYP-500型三轴试验机进行岩石力学实验,借助PCI-2声发射系统记录试件的加载破坏全过程的声发射响应信号;通过声发射振铃计数分析单调加载不同围压、循环加卸载不同围压、单轴不同加载以及三轴不同加载条件下花岗岩声发射特征,发现常规单轴和常规三轴试验岩样声发射规律基本一致;大致均在峰值应力强度的90%左右,声发射累计计数突然增大,可将此作为判定花岗岩破坏的前兆特征;在室内岩石力学试验与现场调研的基础上,基于全应力-应变图,结合冲击能系数判据,确定金源矿区的岩爆倾向性,且用单轴循环加卸载方式来快速判断岩石岩爆倾向性具有一定的参考价值,并可在进一步的研究中将其应用到现场预测当中。

Test field sampling and use TYP-500 triaxial testing machine for rock mechanics test,use PCI-2 acoustic emission system response to damage the whole process of loading of the specimens for acoustic emission signal records;Through the acoustic emission ringing to analysis acoustic emission characteristics under count monotonic loading different confining pressure conditions,cyclic loading and unloading different confining pressure conditions,uniaxial and triaxial loading with different loading conditions,found acoustic emission laws are consistent when rock under the condition of uniaxial compression and confining pressure;Acoustic emission total count increases suddenly in about 90%of the peak stress strength,can judge the granite as precursory characteristics of destruction;Under the indoor rock mechanics test,on the basis of site investigation,based on the stress-strain diagram,combined with the criterion of energy coefficient,determine the rock burst orientation of Jin-yuan mining area,loops and unloading way to quickly determine the rock burst orientation has a certain reference value and apply it to predict the scene in the future.