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Evaluation on the Effect of Relief Wells by 3D Numerical Analysis on the Embankment of an Agricultural Reservoir

농업용 저수지 제방에서 3차원 수치해석에 의한 감압정의 효과 분석

  • Ryu, Jeon-Yong (Department of Ocean Civil Engineering, Mokpo National Maritime University) ;
  • Heo, Joon (Rural Research Institute, Korea Rural Community Corporation) ;
  • Chang, Yong-Chai (Department of Ocean Civil Engineering, Mokpo National Maritime University)
  • Received : 2020.08.24
  • Accepted : 2020.11.02
  • Published : 2020.11.30

Abstract

Through 3D seepage analysis of pressure relief well installed on the embankment of agricultural reservoir, the effects of reducing pore water pressure and hydraulic gradient, and increasing piping safety, depending on diameter (0.2, 0.4, 0.6 m) and space (10, 25, 50 m) of relief well, were analyzed. The conclusions drawn through this study are as follows. i) At the location of pressure relief well, pore water pressure decreases by 25.3~62.5%, and hydraulic gradient decreases by 22.4~55.7%. ii) Between relief wells, pore water pressure decreases by 2.7~40.3%, and hydraulic gradient decreases by 2.8~47.0%, which are relatively less than at the cross section of installed location of relief well. iii) Piping safety factor by critical hydraulic gradient increases by 28.9~125.6% at the location of relief well and increases by 2.9~88.8% between relief wells. iv) Seepage analysis needs to be performed by the 3D method to make evaluation of seepage at the location of relief well and between relief wells possible. v) Additional evaluation is required for various conditions such as waterhead, engineering characteristics of embankment body and its foundation, location, diameter, spacing and depth of pressure relief well.

Keywords

References

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