With the increase of mining depth,the situation of rock burst disaster is becoming more and more serious in the high-stage fully-mechanized caving face of steeply inclined extra-thick coal seam.It is very important to explore the law of overburden movement under the condition of multi-working face of steeply inclined extra-thick coal seam group for safe and efficient mining.Taking Wudong Coal Mine as the engineering background,a three-dimensional physical model test was established.The similar model experiment was used to collect the surface displacement data of the model,and the Matlab was used to draw the overburden displacement cloud map.The laws of whole-cycle overburden movement in the high-stage fully-mechanized caving face of steeply inclined and extremely thick coal seam were revealed,and the relationship between mine pressure and overburden movement in the working face was analyzed.The results are concluded as follows.Firstly,with the increase of mining depth,the vertical displacement of overburden rock evolves from"N"shape distribution to"V"shape distribution from top to bottom.Working face mining is accompanied by overburden fracture and slump,forming a"fracture-slump-self-filling"effect.Secondly,the migration laws of overlying strata of working faces in 43# and 45# coal seam have been obtained,that are coal seam roof caving-direct roof caving-main roof breaking and showing hinged structure,as well as overlying strata slight caving-upper strata serious damage-inter-seam rock pillar overall collapse.Thirdly,before the mining at+550 m level,the support pressure in 43# coal seam is generally greater than that in 45# coal seam.After the mining at+525 m level and+500 m level,the support pressure in 45# coal seam increases sharply.
关键词
急倾斜/特厚煤层/全周期/覆岩运移/矿压规律
Key words
Steeply inclined/Extra-thick coal seam/Whole cycle/Overlying strata migration/Mine pressure law
维普
万方数据