Experimental research of the geo-stress evolution law and effect in the intact coal and gas outburst process

Abstract

Coal and gas outbursts are a potentially fatal hazard that must be managed when mining gassy coal seams. Mining-induced stress plays an important role in outbursts, while elastic potential is accumulated to provide energy for an outburst. In this study, a large-scale true triaxial (LSTT) apparatus was developed to conduct experiments and to understand the outburst mechanism and mining-induced geo-stress evolution law. In the LSTT experiments, coal and gas outbursts resulted from both stress and gas pressure and occurred in a limited balance area. Under the action of mining-induced stress, surrounding rock and coal are compressed. Thus, a large amount of elastic potential is accumulated to provide energy for a coal and gas outburst. Mining-induced stress promotes the development and expansion of the fracture in the coal body, which results in coal wall deformation and damage. The four types of coal wall instability are bodily movement of coal wall, layered separation of coal wall, collapse of coal wall, and break of coal wall. This study develops a classification scheme and management strategies for outbursts.

Coal and Rock Dynamic Disasters: Advances of Physical and Numerical Simulation in Monitoring, Early Warning, and Prevention - Volume II

“…With the continuous growth in energy demand and the increase in mining intensity and depth, the complex interactions among stress, gas, coal and rock have made the geological conditions of mines increasingly complicated, the probability of coal and gas outburst events increases Kursunoglu and Onder, 2019;Ul'yanova et al, 2019). The intricate mining conditions in deep mines give rise to distinct features of coal and gas outbursts, which are marked by heightened energy levels, intensity, and challenges in prevention and control efforts (Odintsev and Makarov, 2020;Gawor and Wasilewski, 2021;Remennikov et al, 2022;Shang et al, 2023). Therefore, studying the evolutionary processes and mechanisms of coal and gas outbursts holds significant importance for the safe operation of coal mines.…”

Experimental study of coal and gas outburst processes influenced by gas pressure, ground stress and coal properties

“…With the continuous growth in energy demand and the increase in mining intensity and depth, the complex interactions among stress, gas, coal and rock have made the geological conditions of mines increasingly complicated, the probability of coal and gas outburst events increases (Li et al, 2019;Kursunoglu and Onder, 2019;Ul'yanova et al, 2019). The intricate mining conditions in deep mines give rise to distinct features of coal and gas outbursts, which are marked by heightened energy levels, intensity, and challenges in prevention and control efforts (Odintsev and Makarov, 2020;Gawor and Wasilewski, 2021;Remennikov et al, 2022;Shang et al, 2023). Therefore, studying the evolutionary processes and mechanisms of coal and gas outbursts holds significant importance for the safe operation of coal mines.…”