In order to protect of buildings and control the ground subsidence in the area of covering thick alluvium,based on the measured data of surface movement and deformation above No. 11011 working face of Zhaogu No. 1 Coal Mine,dynamic changes of surface subsidence curve,surface subsidence maximum velocity,surface movement and deformation duration and lagging distance of maximum subsidence velocity were analyzed with mining under thick alluvium. The results indicated that rapid changes in value of surface subsi...