| The existence of faults has an impact on the distribution state and concentration ways of stress of surrounding rock mass directly,and it may lead to the increasing of tectonic stress especially horizontal stress of coal and rock mass,and it can formate stress concentration easily.At the same time,the existence of fault tectonics has changed the continuity of coal and rock mass media,fault structure areas belongs to weak plane of mechanical system,thus being easy to release energy and providing stress and media conditions to the occurring of rockburst.The geological tectonic background and tectonic evolution processes of Yima mining area has been analysed comprehensively in this paper.With large region viewing,the formation mechanism of the F16fault has been revealed and the characteristic of other geological tectonics had been found out.By researching the stress field of Yima mining area,the direction of the maximum principal compressive stress in modern tectonic stress field of Yima mining area is northeast to northeast-east.Under this stress field,the F16Fault formed in the Indo-Movement, showing tension and torsional state is still live under post-tectonic movement.Mining engineering is the direct occurring reason of fault rockburst.By analyzing the impact on the F16fault from mining engineering and situation of roof stress of25110working face,no matter on the upper plate or lying wall of F16fault,as the working face moving to the fault,the impact on fault plate from mining engineering become larger,thus leading to rockburst more easily.Mining engineering on the lying wall changes the stress state of F16fault plate easier than that on the upper plate of fault.And on the same distance working face to fault,mining on the lying wall can form larger fault slip than mining on the upper plate. Under the influence of F16fault,rockburst is likely to happen at2-1coal seam when tectonic stress,mining engineering and super-thick overlying strata act on2-1coal seam. |
