Using the FLAC3D numerical simulation method, the characteristics of mining stress evolution, fault activation patterns, and fault energy evolution characteristics are simulated and analyzed in the process of the footwall and hanging wall working face heading to a normal fault. The study shows that the fault cut off the mining stress propagation of overlying strata, and the stress blocking effect due to the fault is evident. When working faces head towards a fault, the abutment pressure and the vertical stress of the surrounding rock increase first and subsequently decrease. The abutment pressure of the coal wall and fault is highest when the distances to the fault are 40 m and 30 m for the footwall and hanging wall working faces, respectively. Moreover, the hanging wall mining stress is higher than the footwall mining stress. Fault activation in high-located strata precedes that in low-located strata when working faces head towards the normal fault. Energy is gradually accumulated before unstable fault events take place because of mining, and fault instability quickly releases a lot of energy. The mining stress concentration and fault activation due to faults easily result in rock bursts and mine seismicity, Wu Quan-sen, Jiang Li-shuai and Wu Quan-lin., and Obsahuje bibliografické odkazy
Seismic and rock burst hazards still currently appear to be important in most hard coal mines in Poland. Recently, there has been a significant increase in seismic activity in the Silesian rock mass, in comparison to previous years. In the period 2001-2010, hard coal mines experienced 33 rock bursts. The causes of rock burst occurrences are here presented, based on an analysis of the rock bursts that occurred in Polish hard coal mines. The scale of the rock burst hazard has been characterized with respect to the mining and geological conditions of the existing exploitation. The most essential of the factors influencing the status of rock burst hazard is considered to be the depth of the interval, ranging from 550 m to 1150 m. The basic factors that cause rock burst to occur are as follows: seismogenic strata, edges and remnants, goafs, faults, pillars and excessive panelling. The consequences of rock bursts are damaged and/or destroyed roadways. On this basis, the areas (ranges) of safe zones were selected as being those safe from rock burst hazard in roadways, according to the assessment conducted to establish different degrees of the risk., Renata Patyńska., and Obsahuje bibliografii