摘要
Abstract
In view of the serious deformation and damage problem of heaving floor amount of 580 mm,deformation of two sides of 420 mm,and roof subsidence of 220 mm in the section coal pillar roadway.Based on Mohr-Coulomb constitutive theory and FLAC3D numerical simulation,the stress distribution laws of section coal pillars under mining influence are studied.Through the axial stiffness theory of anchor rods and shear stiffness analysis of anchor net combination bodies,the optimal support parameters for the top anchor rod length of 2.4 m,row spacing of 1.0 m and shed spacing of 1.5 m are determined.Aiming at the problem of expansion,shear dilation,deformation,and plastic rheology,a combined type lateral pressure control technology of adjusting the bottom bifurcation angle of the U-shaped steel shed,optimizing the specification of the bracket and releasing the pressure by opening holes on both sides is proposed.After 3 months of on-site application,the heaving floor amount of the roadway decreases to 210 mm,the deformation of the two sides decreases to 165 mm,the deformation rate decreases from 50 mm/d to 8 mm/d,the stress concentration coefficient decreases from 5.65 to 2.85,the maintenance frequency reduces by 65%,and the support cost saves by 28.6%,which achieves long-term stability of coal pillar roadways.关键词
煤柱/巷道/支护Key words
coal pillar/roadway/support分类
矿业与冶金
