In situ stress test device applied to boreholes with a small aperture and stress field inversion technique in coal mines

Abstract

In situ stress has an important influence on the failure of rock in coal mines, but how to well utilize the test result of in situ stress to guide the engineering is still unclear. The stress to induce coal bursts was analyzed in this study. Based on the test principle of hydraulic fracturing, a quick-test device used in boreholes with an aperture of 31mm was developed to measure the in situ stress. An inversion software was programmed based on the multiple linear regression method to obtain the stress field. Lastly, three engineering cases were presented to introduce the application of the new technique, combining the in situ stress test and stress field inversion. The results show that the new method introduced in this paper is applicable for the evaluation of bursting risk, layout optimization of pre-mining, and mechanism analysis of coal bursts. It has a great significance for the safety of coal mines.