Energy Action Mechanism of Coal and Gas Outburst Induced by Rockburst

Abstract

The essence of both rockburst and coal and gas outburst lies in fast energy release. In order to explore the energy action mechanism of coal and gas outburst induced by rockburst in rockburst and coal and gas outburst combined mines, the split Hopkinson pressure bar (SHPB) experimental device was firstly used to conduct uniaxial impact failure test of coal specimens prone to outburst under different strain rates, and their energy dissipation laws under impact loading were obtained. Next, under the engineering background of coal and gas dynamic phenomena induced by rockburst with different intensities in Xinyi Coal Mine and Pingdingshan Coal Group No. 12 Colliery in Henan Province and Dingji Coal Mine of Huainan Mining Group in Anhui Province, experimental study results were combined with numerical simulation analysis to discuss the energy mechanism of coal and gas outburst induced by rockburst. The study results show that the outburst can be divided into two different processes—critical outburst and outburst—according to the evolution law of outburst energy, and the critical energy conditions for coal and gas outburst are proposed. The minimum destructive energy range for the critical outburst of coal mass is obtained as (5–10) × 104 J/m3. Under some low gas, high stress, or strong disturbance conditions, applied loads can become the main energy sources causing critical failure and even crushing and throwing of coal mass. The coal mass will present an interval splitting structure under dynamic loading, which is obviously different from the failure mode of coal mass under static actions.

Methodical principles of experimental-analytical research into the influence of pre-drilled wells on the intensity of gas-dynamic phenomena manifestations

“…At present, research on the process of development and occurrence of gas-dynamic phenomena consists of storing additional internal energy with subsequent active coal generation as a result of its structure destruction. If we consider the technology of using wells, then this additional internal energy is used for outgassing and reducing the risk of outbursts in coal seams [15]- [17].…”

Dynamic Evolution and Quantitative Characterization of Fractures in Coal at the Eastern Edge of Ordos Basin under Axial Loading

“…In particular, tectonic stress is an essential factor in the distribution and expansion of microfractures in coal seams [4]. With the increase in burial depth, the stress conditions of coal rocks become more complex, resulting in the decline of CBM permeability [5], gas protrusion [6,7], and rock explosion [8,9], which probably enhances the difficulty of CBM exploration. Therefore, it is important to understand the initiation and evolution of the fracture network of coal rocks under different stress conditions, which is vital for exploiting CBM [10] and engineering safety [11,12].…”

Microseismic Signal Characteristics of the Coal Failure Process under Weak-Energy and Low-Frequency Disturbance

“…This has led to an increase in initial stress and significant changes in the mechanical properties of coal and rock, as well as increasingly complex hydrogeological and mining conditions, resulting in increasingly severe accidents [13,14]. Furthermore, rockbursts may produce gas-dynamics phenomena, instantly changing the gas parameters of the mine [15], damaging the ventilation equipment [16] and even triggering secondary accidents such as mine fires [17][18][19], floods [20] and gas disasters [21,22]. Therefore, it is urgent to conduct research on the effective prevention and control of rockbursts in deep mines.…”