3D numerical simulation of elasto-plastic land subsidence induced by groundwater pumping

In this paper, TOUGH2 and FLAC3D are sequentially executed and linked to solve partial coupled three-dimensional land subsidence model, which considers the elastic-plastic deformation behavior, coupled hydro-mechanical effect and the varying nonlinear parameters. The evolution of land subsidence due to constant pumping and pulse pumping is compared to study the strategy of land subsidence control. Results show that: (1) Settlements rebound near the pumping well when stopping pumping, but the land subsidence cone continues enlarge. The plastic deformation can’t recover; (2) Pulse pumping results in fluctuation of the pore pressure, parameters and deformation, but they still dwindle globally; (3) The constant pumping strategy was compared with the pulse pumping with the same pumpage. Under this condition, the plastic deformation decrease with lower pumping rate and small intervals. This is mainly due to the fact that the groundwater level can recover rapidly with lower pumping rate and small intervals. This research provides a new method to simulate land subsidence, and the case study would contribute to the control of land subsidence.