关键词: 采空区, 重复采动, 开采沉陷

Abstract: In order to study the effect of repeated mining on the surface，the observation results of surface movement in the seventh mining area of Nantun Coal Mine were used as the research background to reveal the characteristics of surface subsidence under repeated mining conditions. The results show that re⁃ peated mining changes the distribution characteristics of subsidence. The influence of goaf with short stop mining time on subsidence distribution is more obvious than that with long stop mining time. The side sub⁃ sidence value，subsidence range and subsidence speed of goaf with short stop mining time are larger. Af⁃ fected by multiple repeated mining，the response of surface points to mining is more rapid，which is mani⁃ fested as that the surface movement has only active period and recession period.

Key words: goaf, repeated mining, mining subsidence