The Study Of Influence Law Of Coal Mining On The Whole Displacement Of Shield Inclined Shaft In New-Street Mine Area

ABSTRACT:Shield method has been widely used in various areas of long-distance, large cross-section, nearly horizontal underground tunnel (roadway) constructions both at home and abroad, the technology of which is mature and the experiences are rich. As a brand-new subject, the paper relies on the tube sheet structure inclined mine in New Street, and woks on technical problems of the shield method using in the field of the coal mine construction area.The numerical simulation method, with the use of finite element software MIDAS, is used to analysis associated problems. Specific analysis process is follows:Different models are established to simulate formation structure and successive excavation of inclined shaft and coal seam under the protection of different width of coal pillar. Then check stability by analyzing the segment stress situation.In this thesis, researches on the law of the impact of mining activities to the stability of sheet structure inclined shaft and the determination of reasonable width of protecting coal pillar in New Street mine are carried out. Key research work and the results obtained are as follows:1. As coal seam excavation, slope displacement on the three directions gradually increase. On the horizontal direction along the slope, the whole slope stretch on both sides; on the horizontal direction perpendicular the slope, inclined slightly tilted, and the affect is greater at the bottom of the slope by mining; on the vertical direction, the slope displacement of the center is greater than both sides, and the whole slope looks like the stomach of fish.2. Comparing the slope displacement of three directions, it can be found that the slope based on the vertical settlement, followed by a slight tilt and stretching towards the direction of the strike.3. Based on the simulation of slope segment internal force caused by coal bed mining, the change of the segment safety coefficient was calculated, and then the reasonable width of protecting coal pillar of slope was determined.4. The model of uneven foundation on the elastic beam was established. Then I analyzed the regularity of uneven settlement on the border of fine sandstone and mudstone, both of which the slope passed through.5. Considering the inevitable deformation and dislocation by segment of the slope more than6000meters long. Put forward a method for shield lining segments connecting to resist uneven settlement of the formation.