The Character of Evolution of Rock Fracture Processes from Observations of Acoustic Emission and Time Variations in Radon Volumetric Activity

Laboratory experiments on monitoring the acoustic emission signals and time variations of volumetric activity of radon during uniaxial loading of a granite sample up to its fracture have been carried out. Based on the results of the experiments, the amplitude-frequency spectra of acoustic emission are constructed for four successive time instants. Based on the quantitative interpretation of the data, the time variations in the structural parameters of the rock, the pattern of evolution of the fracture process, and the regularities in the changes of separate stages of this process are studied.