Comparative analysis of options for applying spectral-acoustic method of gas-dynamic phenomena forecasting

The options of applying spectral-acoustic method of controlling stress state of a rock massif for preventing dynamic phenomena are analyzed in the paper. Two options are based on the dependence of relationship of high and low frequencies amplitudes of acoustic signal spectrum of operating equipment on a stress state of a massif in the area between the generator and the receiver of the sound. The difference between these two options is in choosing between high-frequency and low-frequency areas of a source sound spectrum. The drawback of both is in failure to use the whole spectrum of a sound that may cause the error in controlling stress state. To correct this drawback a modified option for applying the method based on the dependence of the median of amplitude and frequency characteristics of a sound on actual stresses is justified. The results of testing the method for controlling stress state of a working face space of a stope in the process of a hard roof directional hydraulic fracturing by hardwaresoftware complex based on RIPAS apparatus are introduced.