1.Mine Safety Technology Branch ,China Coal Research Institute, Beijing ，China； 2. State Key Laboratory of Coal Mining and Clean Utilization, Beijing ，China； 3.Shendong Technology Research Institute,China Energy Investment Group Corp.，Ltd.,Shenmu ，China

To solve the protection problem of surface structures influenced by dynamic subsidence deformation and reveal the dynamic deformation laws of surface subsidence during the movement of surface subsidence, the authors in this paper collected the measuring data from more than 10 surface rock movement observation stations in Dongsheng Mining Area. Based on this, six numerical analysis models were established, considering different mining velocity(2.5～20.0 m/d), the paper analyzed and summarized the characteristics and laws of surface dynamic movement and deformation. The results show that there is a linear relationship between surface movement time , active surface movement period and the longwall depth and propulsion speed ratio; The maximum surface sinking speed and the longwall face propulsion speed are proportional to the square of the product of the maximum subsidence value. However, they are inversely proportional to the square of the mining depth; The ratio between the maximum surface dynamic deformation and the final maximum deformation value of the surface, has an exponential relationship with the ratio between the longwall face advancing velocity and the main influence radius ; The calculation model of the safe mining speed of the longwall face is established based onthe critical deformation value and surface deformation parameters of the protected building, which can calculate the minimum advancing speed of longwall face. Taking the safe mining of coal under high-voltage line tower as an example, the safe recovery speed is given. This example proves that the established calculation model of the safe mining velocityof the longwall face in this paper is effective and provides a technical support for the effective protection of surface structures.

国家自然科学基金面上资助项目（51674142）；中煤科工集团基金面上资助项目（2017MS003）