In the light of the fragmentized coal body in 2315 comprehensive mechanical coal mining face of Chengzhuang Coal Mine, this paper applies the grouting solidifying technology with Malisan N to solve successfully the difficulties existing in the ceiling management in the stoping process.

In the light of the hidden dangers existing in the back production of comprehensive mechanized coal mining face, this paper advances the scheme of reinforcing the fragmentized coal body around the geological structure to assure the smooth completion of the back production of coal mining face.

Based on the results of underground observations and model tests of simulated materials of immediate roof, it is expounded that fragmented roof belongs in cataclastic rock mass,and its caving characteristics is clarified in this paper too.