In order to improve the stability of gob-side entry retaining,the transportation roadway(gob-side entry retaining)of No.1203 working face in Dongrui Coal Mine was taken as the research background,analytic hierarchy process was used to study the main control-ling factors of gob-side entry retaining stability,and it was concluded that the strength of coal body and roadway section supporting strength have the greatest impact on the stability of gob-side entry retaining surrounding rock,with its weight accounting for 59.7%.Based on the main influencing factors,a roof cutting pressure relief plan was designed with a roof cutting height of 5 m and a roof cutting angle of 10°.3DEC numerical simulation was used to determine that the vertical stress of the roadway roof decreased by 7%after the roof cutting.After optimizing the roof cutting section supporting,the development area of the plastic zone on the right roof decreased by 54%,and the development area of the plastic zone on the floor decreased by 37%.After the optimization of the supporting,the cumula-tive deformation of the roof and floor of the temporary supporting decreased by 23.8%,and the cumulative deformation of the two sides decreased by 47.3%;the cumulative deformation of the permanent supporting roof and floor decreased by 3.6%,and the cumulative deformation of the two sides decreased by 26.9%.After cutting the roof and increasing the pre tightening force of the anchor cable in the roadway,the deformation control effect of the surrounding rock in the roadway is obvious.
关键词
沿空留巷/层次分析/切顶卸压/支护优化
Key words
gob-side entry retaining/analytic hierarchy process/roof cutting and pressure relief/supporting optimization