An elastic base beam model of overlying strata movement during coal mining with gangue back-filling
Abstract：A mechanical elastic model of the base beam in a long wall face was constructed using the elastic base beam method. The sinking of the roof rock in the goaf before it touches the waste was modeled by obtaining the basic differential equations for the sinking of the rock. The relationship between the sinking beam and surface subsidence was analyzed by predicting the behavior of the strata. The results showed that sinking of the roof beam is approximately at the maximum after about 10 to 20 meters of working face has been developed. The waste base coefficient was found to be the most important factor affecting roof sinking in the goaf. The pressure on the filling waste changes with the waste base coefficient and the most effective way to reduce surface subsidence is by increasing kg and decreasing W1. It is shown that the control of immediate roof subsidence in the coal seam is the key to controlling surface subsidence. Field experiments showed that W1 could be decreased to about 12 to 64 mm and that the average, maximum surface sink is then 253 ram. This is quite close to the predicted 261 mm sink from the model given a 2.1 meter thick coal seam buried 437 meters deep.
Keywords：gangue back-fillingelasticity base beamstrata behaviorssurtace subsidencean-alytic method
Publication Date：2012-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：6( 14-19 )