Strata movement and surface subsidence prediction model of dense solid backfilling mining

Surface subsidence is the most common disaster in coal mining areas, which threatens human lives and assets. In this study, a prediction model is proposed to predict the surface subsidence caused by dense solid backfilling mining. Firstly, the surface subsidence is monitored by high-resolution survey and its static and dynamic characteristics are analyzed. Then, the universal law of strata movement and load distribution on the main roof are analyzed by similar material simulation and numerical simulation, respectively. The strata movement and deformation of dense solid backfilling mining are totally different from caving mining. There is no caving zone but a limited height of fractured zone developed in the strata. The load distribution on main roof follows the piecewise function. Finally, the prediction model is created based on the combination of elastic foundation beams and volume invariant transfer principle, and the prediction values basically coincide with measured values. This prediction model can provide reference data for the evaluation and management of coal mining hazards.