Study on floor heave control technology of ultra large cross section chamber in underground mine

In order to solve a high floor heave problem of the large cross section powered support reconstruction chamber in WangzhuangMine,a theoretical calculatio n and numerical simulation method were applied to the analysis on the floor deformation and failure features ofthe ultra large chamber. TWo floor heave control technologie s of the reverse arch and floor anchor group reinforcement were provided. TheFLAC3 Dnumerical simulation software was applied to establish a numerical calculation mod el with two floor heave control planes and acomparison was conducted on the support effect. The results showed that the floor failure depth of the chamber was 2. 2 m,the radius of theplastic zone was 12 m,the floor heave control was a big problem and the floor heave control effect of the floor anchor group of the largecross section chamber was obviously better than the reverse arch. The site application showed that after the grouting reinforcement measuresof the floor anchor group conducted,the max floor he ave value was 80 mm and the floor heave could be well controlled.