Experimental study on acoustic emission characteristics of anchor body by bolt-foam aluminum combined support under uniaxial compression

YAO Jingming; TANG Yinghao; WU Yiming

doi:10.13347/j.cnki.mkaq.20250306

Abstract：In order to study the supporting mechanism of rock burst roadway supported by rock bolt-foamed aluminum,uniaxial compression tests were carried out on eight kinds of rock bolt-foamed aluminum combined supporting anchors with different anchor numbers and foamed aluminum thickness conditions,and the mechanical properties and failure mechanism of the anchors under dif-ferent supporting parameters were studied.By extract that acoustic emission characteristic values relate to the rock burst from the acoustic emission signals of the anchored body under different support parameters in the uniaxial compression process,the evolution law of the acoustic emission characteristic values of the anchored body and the correlation between the acoustic emission character-istic values and the support parameters,the mechanical parameters of the sample and the parameters of the rock burst tendency of the sample are studied.The results show that aluminum foam can improve the strength and toughness of the anchor body,improve the elastic energy dissipation capacity of the system,reduce the elastic energy released in the form of mechanical energy in the system,and then improve the ability of the anchor body to resist impact damage;the acoustic emission in count and energy evolution present three-stage characteristics,in which the time proportion of the slow rising stage is positively correlated with the thickness of the foamed aluminum,and the phenomenon of"vertical growth"of the traditional support does not appear during the failure,which in-dicates that the foamed aluminum can effectively restrain the energy mutation by strengthening the rigidity and absorbing energy through large deformation.A quantitative relationship model was established between the acoustic emission parameters and the mechanical parameters,support parameters,and impact tendency parameters.The evolution of the acoustic emission b-value shows three-stage characteristics.The size of the b-value near the failure is linearly correlated with the thickness of the foam aluminum.When the thickness of the foam aluminum is 5,10,15,and 20 mm,the b-values are 0.069 07,0.081 15,0.089 67,and 0.100 25,re-spectively.