Study On Side Abutment Pressure Distribution And Control Measures For Reservation Roadway

After the reservation roadway on the side of the 3-1 coal seam first face in BuErtai mine affected by mining, the surrounding rock damaged seriously. It used integrated of rock mechanics, rock pressure theory, numerical simulation and field test to exploring the relationship of overlying strata spatial structure and side abutment pressure distribution, and superposition of adjacent abutment pressure. Then analyzed the mechanism of reservation roadway abutment pressure impact to failure, and proposed control measures.Field test, it uses the drilling fluid method to get that the fissure height is about 140m, the caving height of 13.16m. After the face was mined over 24m, the side abutment pressure start to increase significantly and continue to increase, it did not reach maximum until 156m. It is analysis result that the face access into full extraction stage when the distance advanced up to 1.27H-1.5H. There is the second structure under the coal seam that is a large cycle of broken roof sinking movement. There are two separate smaller multi-arches on both sides of the walls of waste area. After the key strata fracture, the two separate smaller multi-arches form the large space structure that the feet of arch structure distribute on both sides solid coal of the waste area. All the weight of overlying rock transferred to both sides solid coal of the waste area. The side abutment pressure reach maximum.The width of plastic zone at the side of coal pillar that one side mined is 5.8m-9.5m after calculated. After mining both sides, the coal pillar is basic in the plastic state; its stability is greatly reduced.By the means of analysis on FLAC3D numerical simulation, it got the law of abutment pressure distribution when the rapid face advance and abutment pressure superposition influence of two adjacent faces when different distances between the two adjacent faces. Reservation roadway dear the side abutment pressure with a long period. The stability of adjacent rock will be further reduced, when the front abutment pressure of the back face applied to the reservation roadway. It designed program proposed to layout face and roadway, and selected the distance about 50m-100m. It speed up the face forward to try to reduce the pressure on the abutment time to retain the role of the roadway. Optimize the combined support parameters of the large section roadway; it used bolt grouting to support the roof and two walls at the second support. It reinforced surrounding rock and improved the overall strength of rock by grouting in a timely manner, so restricted broken areas to the depth.Study the side abutment pressure distribution of fast mechanized mining face and control reservation roadway are beneficial to surrounding roadway management and maintenance, at the same time they have important theoretical and practical significance to the high production and efficiency of the mine.