Research On Surrounding Rock Control Of Horizontal Section Fully Mechanized Caving Mining Roadway In Steep Inclined Thick Seam Of Yimen Coal Mine

It is based on engineering geological conditions,the rock mechanics experiment,the engineering analogy,computer simulation and field measurement in the steep thick coal seam of Sichuan Yimen Coal Mine,studied the steeply inclined thick coal seam surrounding rock of roadway deformation law of horizontal sublevel stoping roadways and control technology.The following conclusions are drawn:(1)It is classified as ? hard rock and rock integrity for the basic roof of steeply inclined thick coal seam C1,C2 and C3 in Sichuan Yimen Coal Mine,which is classified as ? hard rock completely of the immediate roof.Coal is ? soft coal which is broken.The directly to the bottom for ? class hard rock,rock mass is complete.(2)The deformation characteristics of surrounding rock are different with different cross section shapes.The results show that when the roadway arranged along the roof side is a right Angle trapezoid section,the roadway deformation is the largest and the semicircular arch section is the smallest.When the roadway arranged along the side of the floor is isosceles trapezoid,the roadway deformation is the largest and the semicircular arch roadway deformation is the smallest.The roof side roadway floor and right side are deformed greatly while the roof and left side are deformed little.The floor side roadway is the opposite.The roadway deformation presents an asymmetric feature.According to the deformation characteristics of roadways with different shapes of sections,the shape of roadway sections arranged along the sides of roof and floor is determined to be semicircular and arched.The row spacing between the coal side bolts on the roof side and the floor side roadway is 600 mm 600mm,and the row spacing between the rock side bolts is 800 mm 800mm.(3)Based on the asymmetric deformation characteristics of surrounding rock of horizontal sublevel mining in steeply inclined extra-thick coal seam,the roadway adopts the non-uniform arrangement of anchor net and cable.Based on the control principle of matching deformation and support,the reasonable support parameters are determined.The non-uniform deformation of roadway surrounding rock is effectively controlled.(4)Field measurement shows that the roof side roadway is mainly deformed by the floor and the right side(coal side),while the roof side roadway is mainly deformed by the left side(coal side).The maximum total deformation of roof and floor of roof side roadway is 58.8mm,and the maximum total deformation of both sides is 58.5mm.The maximum total deformation of roof and floor of the roadway on the slab side is 51.1mm,and the maximum total deformation of both sides is 56.9mm.The roadway deformation is small,and the roadway surrounding rock control effect is good.