摘要:AbstractWhen pumping is conducted in confined aquifer inside excavation pit (waterproof curtain), the direction of the groundwater seepage outside the excavation changes from horizontal to vertical owing to the existence of the curtain barrier. There is no analytical calculation method for the groundwater head distribution induced by dewatering inside excavation. This paper first analyses the mechanism of the blocking effects from a close barrier in confined aquifer. Then, a simple equation based on analytical solution is proposed to calculate groundwater heads inside and outside of the excavation pit with waterproof curtain (hereafter refer to close barrier) in a confined aquifer. The distribution of groundwater head is derived according to two conditions: (i) pumping with a constant water head, and (ii) pumping with a constant flow rate. The proposed calculation equation is verified by both numerical simulation and experimental results. The comparisons demonstrate that the proposed model can be applied in engineering practice of excavation.Graphical abstractDisplay OmittedHighlights•Analyze mechanism of the blocking effects from the barrier in confined aquifer.•Propose analytical models to calculate head distribution inside and outside of the pit in confined aquifer.•Calculate distribution of head for two scenarios of pumping with constant head and constant flow rate.•Analytical solutions verified by numerical simulation and experimental field tests.
关键词:KeywordsenConfined aquiferWaterproof curtainDewateringGroundwater head