THE MECHANICAL PROPERTIES AND FRACTAL CHARACTERISTICS OF THE COAL UNDER TEMPERATURE-GAS-CONFINING PRESSURE.

Deep mining is the most important way to obtain the resource in China now. Thus, rock is the main objective that the deep mining will encounter. Meanwhile, the frequent catastrophes in deep mining such as rock burst, coal and gas bursts, roof caving, water bursts, is the most serious problem. To have a better understanding of the mechanisms of fracture and the laws of damage evolution of rock and coal under deep environment, in this paper, the micro- and meso-scale method is employed to study the behavior of coal under different temperature, confining pressure and gas pressure. Then, the significance of the effect of temperature, confining pressure, and gas pressure on mechanical parameters is analyzed by using the ANOVA method. The fractal study of coal failure pattern by employing the SEM test and fractal dimension was carried out. The fractal dimension of coal fractures was calculated by using the box-covering method. Then, the effects of all factors on the fractal dimension of coal fractures were analyzed. [ABSTRACT FROM AUTHOR]