Study On Strata Behavior Patterns Of Fully-Mechanized Coal Mining To The Dip With Super-longwall And Large Mining Height

Physic-mechanical parameters of coal and rock have been experimented and analysis of geological and mechanical evaluation of rock mass have been conducted according to the geological conditions of No.13-1coal seam in the Liuzhuang Coal Mine, the characteristics of strata behaviors in fully mechanized mining to the dip (FMMD) with super-longwall(280-300m) and large mining height(6.3m) have been studied by the methods that are similar material simulation, numerical simulation, theoretical analysis and field observation based on the above test and evaluation data. And some mining parameters, such as mining depth, mining height, longwall length etc, and large displacement fault have been investigated into effect strata behavior patterns. The abutment pressure evolution characteristics, strata movement characteristics, and the effect of large displacement fault to strata behavior characteristics in FMMD with super-longwall and large mining height were obtained. The influence mechanism with the mining depth, mining height and longwall length for mechanical characteristics of surrounding rock was opened out based on the study of the similar material simulation and numerical simulation. The effect factors of the hydraulic support stability, the coal wall caving and strata pressure characteristics of the affect area of fault were systematically analyzed, and then technology and measures for surrounding rock control of working face and crossing the large fault were put forward. Through industrial test and field observation of strata pressure, results indicate that the strata behavior patterns in FMMD with super-longwall and large mining height have been improved, controlling technology to surrounding rocks stability with complicated conditions have been innovated, and safety and high-efficiency mining of13-1coal seam were achieved. The study could be provided the theoretical support and technical guidance for the safety and high-efficiency mining of the fully mechanized mining with super-longwall and large mining height in the complicated conditions for similar coal mine areas.