This paper examines the effects of borehole arrangement on the failure process of coal-like materials based on its energy\nconversion and acoustic characteristics from the perspectives of energy, AE energy, AE spectrum, and frequency band. Findings\nfrom the study revealed that the presence of borehole can significantly reduce the conversion ratio and growth rate of elastic\nenergy during the loading of coal-like material sample and delay the release of internal energy of the sample. Also, it can reduce the\nfrequency band energy of the main frequency of acoustic emission signal but has little effect on the size and richness of the peak\nfrequency of acoustic emission signal. The practice that makes drilling diameter and depth increase stepwise can minimize the\nelastic energy conversion ratio, the growth rate, and the main frequency band energy of acoustic emission signal of coal-like\nmaterial sample and postpone the internal energy release of the sample to the greatest extent, so as to enrich the richness of the\nsecondary frequency of acoustic emission signal. The results of this study have certain guiding significance for the layout of\npressure relief boreholes in the production process of coal mines.
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