Study on support technology of mine roadway with thick soft and weak composite roof in deep underground mine

According to the support technical problem of the mine roadway with a thick, soft,weak composite roof in a deep section of Chensilou Mine,based on the def ormation failure mechanism of the surrounding rock along the deep mine roadway,with the strong-weak-strong theory and numerical simulation analysis,a gradient combine d support technical plan was provided. The bolt,short anchor and long anchor stage support in the plan could make the roof strata to form a loading reinforced beam.The s hallow borehole grouting within the surrounding rock anchoring zone and the deep borehole grouting in the outside of the anchoring zone could fill the cracks of the surrou_ nding rock within and outside the anchoring zone,could improve the cohesion and internal friction angle of the roof strata and could enhance the integrated stability of the r oof.A site industrial trial and site mine pressure observation were conducted in a railway roadway in South No.9 mining block. The results showed that a max subsidence val ue of the roof in the roadway was 73 mm,a max convergence of the two sidewalls was 147 mm and the subsidence of the roof and the two sidewall deformation of the mine roadway were effectively controlled.