Abstract: Land subsidence caused by groundwater exploitation seriously threatens normal employment and structure safety of buildings, so it is of significance that studying predicting method of land subsidence. Because of the difficulty of the constitutive model and the parameters of soil, and it is not perfect that the land subsidence is computed adopting Biot’s consolidation theory. In the paper, adopting combining methods both mechanics reasoning and statistic mathematics, sets up space-time predicting model research of surface subsidence caused by groundwater exploitation. Firstly, by means of Terzaghi’s consolidation differential equation, the semi-experience predicting model of depicting surface subsidence’s time effect is founded. Secondly, on the basis of analyzing the distribution laws of surface subsidence caused by groundwater exploitation, the space distribution characteristic of surface subsidence caused by groundwater exploitation is studied through the stochastic medium theory. Thirdly, synthetically analyzing the time effect and space distribution characteristics of surface subsidence caused by groundwater exploitation, the time-space predicting model of surface subsidence caused by groundwater exploitation is established. The predicting model totally needs 4 parameters when it finishes prediction. The method of parameters’ computation is introduced. Lastly, the time-space laws of surface subsidence caused by single well’s exploitation is computed and predicted with the predicting model. The research shows that the predicting model can nicely reflect the time and space characteristics of land subsidence caused by groundwater exploitation, and can expediently and rapidly predict land subsidence; and provides theoretical basis for prevention and control of surface subsidence caused by groundwater exploitation.

Key words: Terzaghi’s consolidation theory, stochastic medium theory, time-space predicting model