Abstract:The acoustic emission (AE) technique was used to monitor the triaxial compression process of granite porphyry rock in an iron ore district, and the AE characteristics of the failure process of rock samples were obtained. The Mohr’s envelope was fitted by drawing the stress circle of granite-porphyry, and the cohesion of the sample was 18.68MPa, and the internal friction angle was 54.268°. By analyzing the stress-strain curves of granite porphyry under triaxial compression under different confining pressures and the characteristic curves of acoustic emission energy, event number and cumulative event number, it was found that the initial stress and the fracture breakthrough stress correspond to the first and second peak values of acoustic emission energy and event number. And the peak stress corresponds to the highest peak value of acoustic emission signal. Drawing the fitting line of characteristic stress intensity, it was found that the initial stress of fracture was less affected by confining pressure, and the fracture transfixion stress was greatly affected by confining pressure. The relationship between mechanical properties and AE parameters and rock fracture was obtained, which can provide reference for mining and engineering research with granite as surrounding rock.
