Large Mining High Along The Goaf Floor Heave Mechanism And Control

The paper, encircling the problem of floor heave in gob-side entry driving of large mining height workface, analyses the migration mechanism of overlying formation of fore-and-aft mining, and the stability influence of roof-floor rock, gains the stress distribution of plastically deforming area form the elasto-plastic stability of coal pillar .On the base of realizing the mechanical principle of coal pillar, the paper establishes mechanical model of floor, analyses the stress state of floor, gains the stress-strain and displacement of floor discretional point. The paper analyses the displacement and stress distribution characteristic of coal pillar different width and intensity which influence floor heave, and the influence of surrounding rock different character, analyses the floor heave control effect through reinforcing different part of surrounding rock., opens out the surrounding rock distortion essence of gob-side entry driving from mechanical principle. With whole roadway as a object to reinforce surrounding rock, the paper take effective controlling measure control floor heave. The research has been successfully applied in practice.