Calculation of Floor Deformation in Gob-Side Entry Retaining with Great-Depth and Large-Section

Abstract

Based on the floor heave mechanism in gob-side entry retaining, mechanical model of floor beam in gob-side entry retaining is established. By using the reciprocal theorem, the deflection formula of floor in gob-side entry retaining is derived. The calculated result shows that calculated deflection curve is in accordance with the deformation characteristics of roadway in gob-side entry retaining. The calculated result also shows that the maximum deformation of the floor increases with the increase of the widths of roadway, filling body and limit equilibrium zone of coal side. Finally, measures to control floor heave in gob-side entry retaining is proposed, such as reduction of roadway width and enhance coal-side support.