Author(s): Yongzhou Cheng, Dongwei Yang, Wensen Wang, Dianqi Li
Linked Author(s): Yongzhou Cheng
Keywords: Submarine pipeline, sloping seabed, oblique waves, embedment depth, scour hole
Abstract: Seabed near-shore is undulate, the existence of slopes changed the action characteristics of waves on pipeline and seabed, which will thus affect the scouring below pipeline. Using regular waves with an incident angle of 45� and a median particle size of 0. 22 mm slope, by measuring the width and depth of the scour hole below the pipeline, scour depth and scour evolution under different wave elements and ratio of embedment depth to diameter (e/D) are investigated. The results of the experiments shows that under oblique wave action, the variations of wave height and period has a clear three-dimensional distribution of scour depth along the pipeline, induced the scour depth of right side greater than the left; the scour hole evolved in two distinct stages: rapid and slack. There is a flow tunnel with front and back connected formed below the pipeline while the e/D is less than 1/4, the existence of flow tunnel will enlarge the size of the scour hole, which may inducing the pipeline to be suspended and endanger the safety of the pipeline during operation life cycle
Year: 2017