Abstract：The surrounding rock of roadway is a compound structure consisted of roof，floor and sides. The sides of extraction opening are the weak coal mass，which affect the stability of floor directly. Numerical simulation for influence of the strength of side coal on the floor heave is carried out，which shows that the higher the strength of sides coal is，the lower the degree of floor heave is. So the method of reinforcing sides to control floor heave of extraction opening is proposed in this paper. A practical case proves that the floor heave of deep extraction opening can be controlled to a certain degree by reinforcing sides of roadway.
