Journal of the Korean Society for Marine Environment & Energy (한국해양환경ㆍ에너지학회지)

The Korean Society for Marine Environment and Energy (한국해양환경•에너지학회)
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Scour Protection Effect around the Monopile Foundation

모노파일 기초 주변의 세굴방지 효과에 관한 연구

  • Kim, Seon Min (Department of Naval Architecture and Ocean Engineering, Chonnam National University) ;
  • Kim, Jong Kyu (Department of Naval Architecture and Ocean Engineering, Chonnam National University) ;
  • Kim, Yong Kwan (Korea Fisheries Resources Agency) ;
  • Seo, Seong Ho (Korea Fisheries Resources Agency)
  • Received : 2017.02.09
  • Accepted : 2017.05.19
  • Published : 2017.05.25
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Abstract

In this research, a three-dimensional Computational Fluid Dynamics(CFD), scour characteristics around monopile was grasped and the effect of circular ring type scour protection on reducing protection was assessed. When Torsethaugen(1975) found that the scour area and its depth were coincided quantitatively On the ground of previous findings, after scour was assessed in terms of sea current velocity, we also found that the tendency of maximum scour depth and its width were increased as the sea current velocity was increased. The experiments were performed by attaching ring-circular typed scour protection under the bottom in order to reducing scour around the constructs of monopile type and showed reduced scour approximately by 68.5%. In addition, there were reduction of downward flow and bottom velocities, suggesting that scour protection reduce the effect of downward flow on scour.

본 연구는 3차원 CFD(Computational Fluid Dynamics)이용하여 모노파일 기초 주변의 환형 세굴방지공에 의한 세굴방지 효과를 파악하였다. Torsethaugen(1975)의 수리모형 실험결과를 바탕으로 FLOW-3D의 해석결과를 검증하였다. 검증결과를 바탕으로 유속변화에 따른 세굴을 연구한 결과, 유속이 증가할수록 최대 세굴심과 세굴폭 또한 증가하는 경향을 확인하였다. 모노파일 기초 주변에 세굴방지 효과 연구를 위해 바닥면에 환형 세굴방지공을 부착하여 수치실험을 수행하였으며, 약 68.5%의 세굴 감소 효과를 확인했다. 또한 하강 유속과 구조물 주변 저층 유속이 감소한 것을 확인하였고, 이는 세굴방지공이 세굴에 영향을 미치는 하강류의 저감 효과를 보이는 것으로 판단된다.

Keywords

References

  1. Cho, H.Y., Kim, K.H. and Yang, S.R., 2009, "Local Scour around Submarine Piles due to Waves", J. Inst. Const. Tec., Vol. 28, No. 2, 65-78.
  2. Dargai, B., 1989, "The turbulent flow field around a circular cylinder", Exp. Fluids, Vol. 8, No. 1, 1-12. https://doi.org/10.1007/BF00203058
  3. FLOW SCIENCE, 2014, "FLOW-3D User's Manual, Version 11.0.3".
  4. Kikkawa, H., Fukuoka, S., Iwama, H. and Soogawa, H., 1971, "Study on Scouring around Bridge pier and its Prevention", J. JSCE, Vol. 1971, No. 194, 83-90.
  5. Ko, D.H., Jeong, S.T. and Oh, N.S., 2015, "Numerical Simulation Test of Scour around Offshore Jacket Structure using FLOW-3D", J. Korean. Soc. Coast. Ocean. Eng, Vol. 27, No. 6, 373-381. https://doi.org/10.9765/KSCOE.2015.27.6.373
  6. Neill, C.R., 1968, "Note on initial movement of coarse uniform bed material", J. Hydrulic. Res., Vol. 17, No. 2, 247-249.
  7. Oh, M.H., Kwon, O.S., Jeong, W.M. and Lee, K.S., 2012, "FLOW-3D Analysis on Scouring around Offshore Wind Foundation", J. Korea. Acad. Industr. Coop. Soc., Vol. 13, No. 3, 1346- 1351. https://doi.org/10.5762/KAIS.2012.13.3.1346
  8. Olsen, N.R.B. and Melaaen, M.C., 1993, "Three-Dimensional Calculation of Scour around Cylinders", J. Hydraul. Eng., Vol. 119, No. 9, 1048-1054. https://doi.org/10.1061/(ASCE)0733-9429(1993)119:9(1048)
  9. Richardson, E.V. and Davis, S.R., 1995, "Evaluating scour at bridge", FHWA Rept. HEC-18, U.S. Dept. of Transportation, Federal Highway Administration, Washington, D.C.
  10. Shin, C.H., 2011, "A Study on Local Pier Scour Reduction Using 3D Numerical Simulation", Hanyang University Master's thesis, 1-56.
  11. Shin, S.H. and Hong, K.Y., 2004, "An Experimental Study of Sediment Transport Patterns behind Offshore Structure", J. Korean Soc. Mar. Environ., Vol. 7, No. 4, 207-215.
  12. Son, A.L., Kim, B.H., Moon, B.R. and Han, K.Y., 2015, "An Analysis of Bed Change Characteristics by Bed Protection Work", J. Korean. Soc. Civ. Eng., Vol. 35, No. 4, 821-834. https://doi.org/10.12652/Ksce.2015.35.4.0821
  13. Son, K.S., 2014, "Investigation of Reduction Methods for the Local Scour around the Cylindrical Pile in the Wave Fields", Chungbuk National University Doctor's thesis, 1-123.
  14. Sumer, B.M., Christiansen, N. and Fredsoe, J., 1993, "Influence of Cross Section on Wave Scour Around Piles", J. Waterw. Port. C., Vol. 119, No. 5, 477-495. https://doi.org/10.1061/(ASCE)0733-950X(1993)119:5(477)
  15. Torsethaugen, K., 1975, "Local crosjonved store konstuksjoner Model lforsok (Norvcgian)", Vassdragsog Havne-laboratoriet, Trondheim.