Evolution and control technology of energy aggregation and dissipation of a high hard roof during breakage and destabilization

Abstract

The focus of this study was prevented disasters caused by the breaking of high hard roofs (HHRs) in mines. A model of the mining load-bearing capacity of a HHR cantilever beam structure (HHRCBS) was developed based on elastic foundation beam theory. The evolution of mining load-bearing capacity and energy aggregation and dissipation in HHRs were analyzed. Additionally, the dynamic working resistance experienced by hydraulic supports was quantitatively decomposed from an energy perspective. The findings indicated that (1) during mining operations, the pressure and strength of the working face were primarily governed by the stability of the HHRCBS. (2) The cantilever length significantly influenced the evolution of mining load-bearing capacity and energy aggregation and dissipation in the HHR. By reducing the length of the cantilever beam in the HHR, the effects of roof breakage on the cantilever beam structure were significantly decreased. (3) The dynamic load of the overburden and the energy released by the breakage of the HHR corresponded to 7536.1 kN, while the static load generated by the breaking of low rock blocks was 8348.3 kN. We then analyzed an integrated surface control technology for HHRs and conducted a field test in the Datong Mining District. The measured dynamic working resistance showed that the proposed integrated surface control technology could effectively prevent strong pressure during mining.