Research and application of mechanical models for the whole process of 110 mining method roof structural movement

Abstract

For the 110 mining method, it is challenging to accurately calculate the support resistance of the roadway due to the lack of understanding of the dynamic movement of the overlying strata in this method. The consequential excessive support results in a significant increase in the cost of roadway support. The authors explored the overlying strata movement and roadway deformation of the gob-entry retaining in the 110 mining method to solve this problem. First, the typical stages of the roof-cutting gob-side entry were defined. Second, the mechanical model and calculation formula of the support resistance on the roof were explored. Then, using numerical simulation software, the starting ranges of the specific supports at different stages were verified and the feasibility of the support scheme was examined. Finally, combined with the field measurement data, the stress and the deformation of the gob roadway at different stages under the influence of two mining processes in the 110 mining method were obtained. The numerical simulation results obtained are consistent with the field test results, providing a theoretical basis for precision support at different stages by the 110 mining method.

Keywords

110 mining method / gob-side entry retaining / roof structure movement / mechanical model

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