Study On The High Efficient Development Manner Of Groundwater In Yellow River Valley With Thin Aqufier

Suide County is an important part of the energy and chemical base in the north ofShaanxi Province.In recent years,the lock of water resource has become a major constraintto develop the local economy and the base.The aquifer in Zaolinping valley which is on theright bank of the Yellow River is mainly composed of the loose bed of quaternary system andthe underlying bedrock weathering zone.It has the water supply significance because of thevery strong permeability to water and the superior condition of groundwater recharge.However, the aquifer’s thickness of quaternary system in the valley is thin, in order to provideSuide County Industrial Park with guaranteed water supply, it is very important to chooseappropriate intake structures for groundwater for the sake of exploiting groundwaterreasonably and efficiently.The common intake structures for groundwater include conventional well, generallarge-diameter well, gallery, radial collector well and horizontal seepage well. In this thesis,two-dimensional finite difference numerical models of conventional well andthree-dimensional finite difference numerical models of non-casting-well intake structure aremodeled, which are on the basis of the theory of coupled seepage–pipe flow model proposedby Chen Chongxi. The best manner of exploiting groundwater for each water intake structureare determined by analyzing the results of different schemes of each water intake structurethrough efficiency and water yield. Then, groundwater’s allowable yield and the best mannerof different intake structures in this region are determined On this basis, the structure andlayout of the recommended manner of exploiting groundwater are optimized by researchingand analysing the influence factors of water yield.Through the establishment of numerical models of conventional well, gallery, radialcollector well and seepage well, groundwater’s allowable yield of various schemes iscalculated separately, finally we draw conclusions that the efficiency and water yeild of thenon-casting-well intake structure such as gallery, radial collector well and seepage well aredistinctly better than that of the conventional well; Seepage wells is the best manner of exploiting water in the research region,when it is used, the groundwater’s allowable yield inaverage water season of yellow river is66115.32m3/d, and the yield is49131.57m3/d in lowwater season.Through demonstrating on guarantee rate, the groundwater’s allowable yieldcan be guaranteed. Total water yield is more when the chamber of seepage well is laid alongthe water edge of low water season than that along the water edge of average waterseason;with the increase of the pore diameter and the length of the pore extending into thequaternary system,the water yield of seepage wells increases,but the rate of increasedecreases;in when the total number of chambers is equivalent, the greater the number ofseepage wells is,the more the water yield is,but the less-number project is convenient forwater collection and management; the water yield of the optimization scheme of seepage wellin average water season is102660.51m3/d,and the yield is78122.28m3/d in low water season.