Journal of Korean Society of Coastal and Ocean Engineers (한국해안해양공학회지)

Korean Society of Coastal and Ocean Engineers (한국해안·해양공학회)
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Characteristics of the Local Scour Around Submarine Imbeded Pipelines Due to Waves

파랑에 의한 해저 매설관로 주변의 국부세굴특성

  • Kim Kyoung Ho (Department of Civil Engineering, Chung-Buk National University) ;
  • Kim Hong Hoon (Department of Civil Engineering, Chung-Buk National University) ;
  • Oh Hyoun Sik (Department of Civil Engineering, Chung-Buk National University) ;
  • Yeun Ju Heum (Department of Civil Engineering, Chung-Buk National University)
  • Published : 2005.06.01
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Abstract

It is well-known that when pipelines are positioned on a sandy seabed, they have a tendency to bury themselves. This paper presents the results of an experimental investigation on the characteristics of the local scour around the submarine imbeded pipelines exposed to waves. Scour depths were measured according to the imbedment ratios of the pipelines. The results indicated that the effect of lee-wake of the pipe is the key element in the scour process of the submarine imbeded pipelines. In general, scour depths are smaller as the imbedment ratios are larger. Using the experimental results, the relative scour depths are related to Keulegan -Carpenter number and modified Ursell number, and the empirical equations are established. These equations show that the relative scour depths are proportional to above two parameters and the scour region is extended as Keulegan-Carpenter number and modified Ursell number are larger.

사질성 해저바닥 위에 관로가 설치되는 경우 자가매몰 되는 경향이 있는 것은 잘 알려진 사실이다. 본 연구는 해저에 매설된 관로 주변의 국부세굴의 특성을 실험적으로 고찰한 논문이다. 관로의 매설비에 따라 국부세굴심을 측정하였다. 관이 매설된 경우의 국부세굴에서는 배후류가 세굴에 큰 영향인자로 작용하는 것으로 나타났다. 일반적으로 세굴심은 매설비가 클수록 감소하는 경향을 나타내었다. 실험결과를 이용해서 상대 세굴심과 K-C수 및 수정 Ursell수의 상관성을 알아보고 이들의 관계식도 도출하였다. 실험결과 K-C수 및 수정 Ursell수가 증가할수록 세굴영역이 확장되고 세굴심이 증가하는 것으로 나타났다.

Keywords

References

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