Research On Complexity Of Mining Process For Steeply Dipping Nonlinear Fully Mechanized Face

Due to the violent effect of the crustal movement,the level or near horizontal coal seam of the original sediment is uplifted or sagged or fractured and then rotated to form steeply dippping(most people tend to 35°-55°)coal seam.The bottom layer of the coal seam is mostly oncave or convex syncline and anticline,which leads to the complexity of coal cutting in fully mechanized face with steeply dippping coal seam has increased sharply compared with straight fully mechanized face.The coal mining machine cuts the coal from the straight-line fully mechanized face into the steeply dippping concave or convex nonlinear fully mechanized face,and the automatic"cuting floor and remaining roof"or"cuting roof and remaining floor"phenomenon occurs,with the accumulation of the"remaining roof and cutting floor/cutting roof and remaining floor",the curvature of the arc segment section of the fully mechanized face gradually increases,resulting in deterioration of the stability of the support,the armored face chain conveyor(AFC)is suspended,and even the support dumpling,connector of AFC is broken,and fully mechanized face is stopped.It is necessary to study the coal cutting process of steeply dippping concave or convex nonlinear fully mechanized face to ensure the reasonable curvature of the face and maintain the normal production of the face.At the same time,it is also useful for the optimization of coal cutting process in fully mechanized face with non steeply dippping coal seam floor undulation.In actual production,the steeply dipping nonlinear fully mechanized face has a large amount of coal,and it is difficult to accurately measure cuting floor or the remaining floor.In this study,a computer dynamic simulation method is used based on the main structural parameters of the shearer and AFC and the dip angle of the face,a simulation model is established,and the steeply dipping non-linear face coal cutting multi-frame map can be drawn proportionally,and then the detailed process of nonlinear coal cutting can be visually demonstrated by Flash,which can demonstrate visually complete process of nonlinear coal cutting and more accurate value of cutting floor or the remaining floor can also be obtained.The simulation method overcomes the shortcomings of the difficulty and error of establishing a mathematical model for cutting or remaining the floor and the inability to visually demonstrate.Based on the example of steeply dippping coal seam mining,this paper analyzes the basic characteristics of the complexity of coal cutting process in nonlinear fully mechanized face.Based on the simulation results,the law of coal cutting in nonlinear fully mechanized face is summarized,and reveals the influence of coal cutting on the non-linear fully mechanized face on the support and the AFC,and discusses the complexity of the relationship between the three is discussed from the perspective of system complexity,and its interaction mechanism such as feedback,coordination.The main findings are as follows:(1)The particularity of coal cutting with steeply dippping nonlinear face is discussed,and the basic characteristics of complexity are described from the perspective of system complexity.On this basis,the steeply dippping nonlinear face quantitative model is established,and the quantitative model is used to quantitatively simulate the coal cutting on the nonlinear face,which provides a basis for guiding the on-site optimization of the coal cutting process to adapt to the floor undulation or the fully mechanized face.(2)The the overcutting or undercutting volume of the steeply dippping nonlinear face are analyzed,and the remaining roof and cutting floor/cutting roof and remaining floor rules of the steeply dippping nonlinear face are revealed.At the same time,the main factors affecting the overcutting undercutting value of the steeply dippping nonlinear fully mechanized face are analyzed,and the complexity of coal cutting is quantified.(3)Based on the quantitative simulation results and the state of the support and the AFC after coal cutting,the influence of the steeply dippping nonlinear face on the support and the AFC was analyzed,and the associated complexity between the coal cutting,the moving support and the pushing AFC was explained.(4)The technical solutions of optimizing coal cutting,stabilizing the support and reducing the failure of the AFC is put forward,and it is applied to the field practice to guarantee the continuously normal advancement of the steeply dippping nonlinear face.