Study On Influences Of Laws On Rock Pressure And Roof Movement Made By The Fault In Larege Mining Height Fully Mechanized Face

The fault, a common geologic structure, which would destroy the continuity and integrity of the roof strata if it existed, led to support pressure rising and overlying rock moving severely when the working face went through it. However, it was more obvious that large mining height resulted in increasing falling height of the roof because of the increased mining height. If the fault existed, it would make face timbering harder and the probability of roof accidents more regular. Therefore, it was completely important to research and analyze neighboring pressure and the variation law of roof strata.In the paper, setting in geological conditions of Wangzhuang coal mine 8101 face, we did the similar material simulation experiment and built 3 normal faults, F1, F2 and F3 with an angle of 30 degrees on average and fault throw of 3.5 meters. Two normal faults, F1 and F3 were pushed from hanging wall to foot wall, while the normal fault F2 was pushed rightabout. F1 was a contrast to F2 and F3 validated the experiment. Large mining height was separately pushed from hanging wall and foot wall to study neighboring pressure and the variation law of roof strata. Thereinto, the variety of rock pressure was monitored by the holder of pressure senior, while the variety of roof strata was mainly showed by falling height, fissure development and fault slippage.In the similar material simulation, when working face was separately pushed from hanging wall and foot wall, we researched and analyzed suppot dynamic pressure variation to observe that periodic weighting and roof falling had an influence on poppet pressure. To compare the support pressure dynamic changes between hanging wall and foot wall when the working face closed to the fault, analyzed the influence of support pressure change by the fault with different tendencies.What’s more, we made a discussion mainly on how extraction speed and support setting load affected poppet pressure and pressure developing vaule of support.According to the same geological conditions of Wangzhuang coal mine 8101 face,Using FLAC 3D numerical software, we built relevant models to imitate large mining height going through the fault by hanging wall and foot wall respectively. We calculated roof stress in working face and the deflection of the roof, which checked related conclusion in the similar material simulation. We also calculated change laws on advanced support stress and stress distribution in front working face, stress field in the fault slip and stress field in the fault surface, which replenished in-situ stress distribution near the fault. Besides, when physical-mechanical properties of rock stratum, mechanical property of layer section, fault slippage, shared force edge of models remained the same, we built 5 models separately with high-angle fault of 0 degree, 45 degrees, 80 degrees, 90 degrees. We did the research that different co-hades had an affection on peak stress in the front of working face and roof stress in the mining working face.Basing on further analyzing relative conclusions of neighboring pressure and the variation law of roof strata, when wangzhuang coal mine 8101 face went through the fault, we put forward a program which defined some related technical measures, parameters and construction technology.