Unified Mechanism of Rock Burst Induced by Coal Mine Earthquake and Its Activity and Response Characteristics

Abstract

The occurrence regularity of the coal mine earthquake under the influence of hard roof, fault, and mining was studied by theoretical analysis, field investigation, and monitoring data analysis for the phenomenon of rock burst induced by coal mine earthquakes. The dissipation characteristics of coal mine earthquake energy propagation considering a hypocenter scale were described, and the coal mine earthquake response characteristics were analyzed. The two principles of rock burst induced by hard rock fractured type coal mine earthquakes and the three principle of rock burst induced by fault were described. Based on this, the unified mechanism rock burst induced by different types of coal mine earthquakes was proposed. The results show that the microseismic energy increases sharply and decreases sharply when mining in the fault area. The amplitude and frequency of support resistance increased before and after the heavy coal mine earthquake occurred. The periodic characteristics of the coal mine earthquake in the 43upper 13 working face of the Dongtan coal mine show that there are 50 m small periods within 100 m large periods. The multiparameter field monitoring can make it possible for instantaneous capture of the coal mine earthquake dynamic responses. The unified rock burst mechanism induced different types of coal mine earthquake and is the difference energy between the superposition energy of the rock burst source region and the energy consumed by coal-rock instability increases suddenly under the action of coal mine earthquakes. Meanwhile, the violent rock burst accident occurs when the stiffness condition is satisfied.

Mechanism and Empirical Study of Rockburst in the Adjacent Area of a Fully Mechanized Top-Coal Caving Face Based on Microseismic Technology

“…Let the load of the hanging part of key stratum i be q i , then the load transferred to the coal body on one side of the goaf is Q i = q i /2. q i is calculated as shown in Equation (2).…”

“…The reason for this is that with the depletion of shallow coal resources in China, coal mining is characterized by an increasing mining depth, more extensive underground excavation, and more frequent coal pillar mining. This leads to increasing difficulties in coal mining and frequent occurrences of dynamic disaster accidents [1][2][3][4]. In addition, compared to China, other countries may experience fewer rockburst accidents, but the resulting damages and associated mine disasters, such as roof fall and roof caving in longwall mining faces, should not be overlooked [5].…”

Research on the Laws of Overlying Rock Fracture and Energy Release under Different Mining Speeds

“…A significant relationship exists between the advancing speed of the working face and the energy release within the stope [13]. The unpredictability of the underground rock mass environment has led to a limited number of theoretical studies on the energy release of surrounding rock during coal mining [14][15][16][17][18]. At present, the connection between the advancing speed of the working face and energy release is predominantly investigated through microseismic energy monitoring [19].…”