Laboratory Study On Three-dimensional Drawing Under Inclined Wall Conditions

The flow process of caved ore rocks is greatly changed due to the limitation of the inclined boundary condition when the inclined medium-thick ore body is mined with sublevel caving method.In this paper,The indoor physical ore drawing experiment is carried out considering the influence of dip angle of ore body,and the flow regularity of three-dimensional ore drawing of inclined wall was studied.The main results are as follows:(1)The flow zone of granular particles is simplified into three parts:non-influenced area,transition area and inclined wall control area.The flow axis was correspondingly divided into three parts with lower,middle and upper flow axes.The main features are as follows: the flow axes in different areas are distributed in different Spaces;the lower flow axis is slightly deviated from the axis of the draw point;the angle between the central flow axis and the axis of the draw point increases;the upper flow axis is almost parallel to the upper inclined wall.The length of the lower flow axis increases and the upper flow axis decreases,while the middleflow axis remains the same.(2)The main characteristics of the draw body are as follows: The forms of the draw body vary with the change of the ore drawing height.In the non-influenced area,the draw body is cut by the ore draw point and the front wall,and it is three unequal axial ellipsoid body.In the transition area,the draw body begins to be cut by the inclined wall,and the cutting of the draw body by the upper inclined wall is gradually larger than the front wall with the increase of the ore drawing height.Under the influence of upper inclined wall,the degree of the body is no longer changed,and the form of the body is no longer an incomplete ellipsoid and its morphology changes greatly with the increases of draw height.(3)According to the analysis of the draw body of different inclusions based on discharged quantity,the movement modes of the particles are mainly translation and rolling in the non-influenced area,and the shape of draw body almost coincides.In the transition zone,with the increase of the angle of the ore body,the transition range of the draw body increase.In the inclined wall control area.,the flow diversion function of the inclined wall is larger than that of the front wall,and the particles is mainly sliding.As the angle of ore body decreases,the cutting volume of the inclined wall on the draw body increases.(4)The influence of angle of ore body on residual body.According to the mining characteristics of the ore can be divided into the upper wallresidues,the foot wall residues and the fringe residues.Due to the deficiency of angle of ore body,the volume of the residual body decreases with the increase of the dip angle of the ore body,and the residual volume of each part corresponding to different dip angle of ore body is different...