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JDR Vol.11 No.5 pp. 989-994
(2016)
doi: 10.20965/jdr.2016.p0989

Paper:

Experimental Study on 3D Scour Around an Embedded Submarine Pipeline Under Oblique Waves

Dianqi Li*, Yongzhou Cheng*,**,†, Yu Yao*,**, Xunxiao Li*, and Xianhe Lu*

*School of Hydraulic Engineering, Changsha University of Science and Technology
Changsha 410114, P. R. China

Corresponding author,

**Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province, P. R. China

Received:
June 17, 2016
Accepted:
July 14, 2016
Online released:
October 3, 2016
Published:
October 1, 2016
Keywords:
submarine pipeline, scour hole, sloping seabed, oblique waves, embedment depth
Abstract

Wave deformation on a sloping seabed and the incident angle of waves greatly influence local submarine pipeline scour. Most previous studies on such scour considered wave deformation but not incident wave angle. Using regular waves with an incident angle of 45°, we investigated 3D scour around an embedded submarine pipeline under oblique waves in experiments. After examining wave deformation near the pipeline at different embedment depths, we analyzed how seabed scour evolved around the pipeline. Results of experiments showed that under oblique wave action, pipeline embedment depth affected wave height on both seaside and leeside of the pipeline. A 3D scour hole occurred under the pileline when the ratio of embedment depth to pipe diameter (e/D) was less than 1/4. Different forms of sand ripples also occurred on both sides as e/D changed. The embedment depth also determined the rate at which scour developed. The scour hole evolved in two distinct stages: rapid and slack. The scouring rate on the right side of the pipeline was greater than that on the left during the rapid phase, leading to an imbalance in scouring depth between the two sides.

Cite this article as:
D. Li, Y. Cheng, Y. Yao, X. Li, and X. Lu, “Experimental Study on 3D Scour Around an Embedded Submarine Pipeline Under Oblique Waves,” J. Disaster Res., Vol.11, No.5, pp. 989-994, 2016.
Data files:
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Last updated on Dec. 05, 2019