Rational Anchoring Parameter Analysis Of Coal Rock Bolt Supporting In The Upper Part Of Deep Coal Roadway

With the continuous development of coal mining industry,the depth of coal mining is increasing,which brings new challenges and difficulties to the coal mining industry.The primary problem in deep coal roadway mining is the reasonable and safe supporting of roadway.Firstly,the main factors affecting the stability of deep coal seam(original rock stress,anchorage strength and anchorage length)were determined,and the mechanical parameters of rock physical properties were measured through related experiments.Then,an appropriate FLAC3 D numerical model is established to divide the grid and select the direction of a A for analysis.This article focuses on a different original rock stress(8 mpa,14 mpa,20 mpa),different anchoring strength intensity of(1,2,3,4 strength,strength strength strength 5),different anchoring section number(anchor,anchor,anchor 2paragraphs 1 3,anchor,anchor 4 paragraphs 5)down conditions analysis of deep roadway help department on the horizontal displacement of surrounding rock,displacement gradient variation characteristics.Through numerical simulation and data processing using TECPLOT software and ORIGIN software fitting,the relation curve between the distance from the center of the roadway and the change of displacement amount of surrounding rock in the horizontal direction was obtained under the above conditions.Through comparative analysis of the obtained data,the following conclusions can be drawn:(1)under the condition of the same anchorage strength and the same anchorage length,with the gradual increase of original rock stress,the horizontal displacement of surrounding rock of roadway section increases significantly,showing a positive correlation.(2)under the conditions of the same original rock stress and the same anchorage length,it is found by changing the anchorage strength: with the increase of the distance from the center of the roadway,the horizontal displacement of the surrounding rock in the upper part of the roadway decreases exponentially,so it can be determined that the anchorage strength has a significant impact on the supporting effect of the surrounding rock.Under the condition of the same original rock stress and the same anchorage strength,by changing the anchorage length,it is found that,with the increase of the distance from the center of the roadway,the horizontal displacement of the surrounding rock of the upper part of the roadway decreases exponentially,so the anchorage length has a significantimpact on the supporting effect of the surrounding rock.(3)when the anchoring strength value is small,by changing the number of anchoring section,found that the help of surrounding rock of roadway in the horizontal displacement of small changes or don't change,when anchoring strength value is bigger,by changing the number of anchoring section,found that the help of surrounding rock of roadway in the horizontal displacement of change also small changes or not,only when the anchoring strength value is moderate,by changing the number of anchoring section,help the surrounding rock of roadway in the horizontal displacement of change.With the uniform increase of the number of anchorage sections,the displacement of surrounding rock in the roadway section gradually decreases.