Study on Mechanical Behavior and Seepage Characteristics of Coal Mass during Unloading

Abstract

With the increase of buried depth, the content of gas increases gradually. The gas in the mining process will lead to gas gush and other dynamic disasters, or even coal and gas gushing in front of the working face. Therefore, the study on the permeability distribution of coal and the surrounding rock is the core work of coal and gas mining at the same time. To study the mechanical behaviors and seepage characteristics of coal mass during unloading is to prepare for coal and gas mining in the future, which can not only ensure the safety of operators to the maximum extent but also increase the mining rate as much as possible. Based on the stress-strain curve and seepage curve, the brittleness index and seepage characteristics of coal are analyzed. The greater the brittleness index is, the more likely the coal mass is to produce cracks, and then to form large cracks, or even fracture. Through the study of brittleness index and seepage characteristics of coal mass, the mechanical behavior of coal mass can be easily obtained, so as to guide the mining of coal mass.

Experimental Study on the Variation Mechanism of Permeability and Seepage Characteristics of High-Rank Coal with Different Bedding

“…Nowadays, the experiments on the seepage characteristics of coal are mainly carried out from different stress loading conditions, different types of coals, different seepage media, etc. − Among them, most of the experiments that study the relationship between coal permeability and stress. − Such as triaxial seepage tests can be carried out to reveal the seepage characteristics of coal under triaxial stress; − It can also study the evolution mechanism of coal permeability by controlling the cyclic load; − different loading conditions can also be designed to study the seepage characteristics of coal under different stress environments. , In addition to the stress experimental study, there are experimental studies that analyze the relationship between the water saturation of coal and the effective stress coefficient and stress sensitivity by controlling the different water saturation of coal and comparative seepage experimental studies that control different seepage media. , These experimental studies can reveal the seepage characteristics of coal. However, it can be seen that these experiments are all based on the external environment of coal.…”