Title: Identifying the optimum location of the dewatering pumping wells around excavations using numerical FEFLOW model: a theoretical study
Authors: Hayder H. Kareem
Addresses: Structures and Water Resources Department, Faculty of Engineering, University of Kufa, Al-Najaf, Iraq
Abstract: A theoretical study has been explored the dewatering process in an excavation pit has dimensions (600 × 600) m2 and depth 6 m in an area (4,000 × 4,000) m2 with a total depth 30 m using FEFLOW programme. A mathematical model is created to reduce the water table at least 1 m below the bottom level of the excavation. The model is run in the steady state (one year) and transient flow (45 days, 60 days, 90 days and 120 days) conditions. Pumping wells are installed at distances of 50 m, 100 m, 150 m, 300 m, 450 m and 600 m away from the excavation. The total tested scenarios are 27: 15 (steady state) and 12 (transient state). Only 13 scenarios succeeded in achieving the required condition: 4 (steady state) and 9 (transient state). Economically, over the succeeded scenarios, scenario (S16) is considered the best dewatering one with the lowest extraction rate (157,500 m3/45 days) and minimal distance away from the excavation (50 m).
Keywords: construction excavation pit; dewatering; FEFLOW; optimum location; mathematical modelling.
DOI: 10.1504/IJHST.2024.140311
International Journal of Hydrology Science and Technology, 2024 Vol.18 No.2, pp.140 - 154
Received: 04 Aug 2022
Accepted: 15 Mar 2023
Published online: 02 Aug 2024 *