1993 Fiscal Year Final Research Report Summary

Study on Optimal Pumping Design for Dewatering of Deep Excavation Site in Multilayred Aquifers

Research Project

Project/Area Number	04650440
Research Category	Grant-in-Aid for General Scientific Research (C)
Allocation Type	Single-year Grants
Research Field	基礎・土質工学
Research Institution	Okayama University
Principal Investigator	KOHNO Iichiro Okayama Univ., Faculty of Engineering, Professor, 工学部, 教授 (00025941)
Co-Investigator(Kenkyū-buntansha)	TAKESHITA Yuji Okayama Univ., The Graduate School of Natural Science and Technology, Lecturer, 大学院・自然科学研究科, 講師 (90188178)
Project Period (FY)	1992 – 1993
Keywords	Pumping design / Dewatering method / Deep well method / Groundwater
Research Abstract	An optimal design method is presented for dewatering a excavation site. It predicts the optimum number of deep wells, their locations, and the rate of pumping needed to maintain ground water levels below specified elevations at steady and unsteady state. In our proposed method a linear programming method is used to determine the pumping rate at steady state and AIC is used to suggest the optimum deep well locations. This is accomplished by including the finite element analysis of two-dimensional steady seepage flow. Nonlinear least-squares algorithm incorporating finite element analysis of unsteady seepage flow is used to compute the pumping rate required to reach ground water levels below appointed elevation in a prescribed time. The method is applied to several examples of dewatering for a large excavation site in unconfined aquifer models.