Experimental investigation of the equilibrium scour depth below submerged pipes both in live-bed and clear-water regimes under the wave effect. (November 2018)

• Record Type: Journal Article
• Authors: Dogan, Mustafa; Ozgenc Aksoy, Aysegul; Arisoy, Yalcin; Guney, Mehmet Sukru; Abdi, Vahid
• Is Part Of: Applied ocean research. Volume 80(2018)
• Page Start: 49
• Page End: 56
• Publication Date: 2018-11
• Subjects: Wave -- Submerged pipe -- Scour regime -- Equilibrium scour depth -- Empirical equations -- Experimental measurements; Ocean engineering -- Periodicals; 620.416205
• DOI: 10.1016/j.apor.2018.08.010
• Languages: English
• ISSNs: 0141-1187

Abstract

Highlights: Equilibrium scour depth below submerged pipelines was studied for both clear-water and live-bed scour regimes. Experiments were conducted with different grain sizes of bed materials. The relative equilibrium scour depth is related to Keulegan-Carpenter number for clear-water scour regime. The relative equilibrium scour depth is related to both Keulegan-Carpenter number and Shields parameter for live-bed scour regime. New equations were suggested for clear-water and live-bed scour regimes, including the most important non-dimensional parameters. Abstract: Pipelines are the key structures to carry fluids such as oil, petroleum, gas and water; any inadequate design induces bottom stability problems causing unintended consequences. In the present study, the equilibrium scour depth below submerged pipes due to regular waves was investigated experimentally. During the experiments various pipe diameters, bed material grain sizes and wave characteristics were used. The novelty of the study is that the experiments were performed both in live-bed and clear-water regime conditions. The analysis of the experimental data showed that the equilibrium scour was correlated with Shields parameter as well as Keulegan-Carpenter number, especially for live-bed scour condition. However, in the case of clear-water scour, the Keulegan-Carpenter number was found as a unique non-dimensional parameter that dominates the scour phenomenon. New empirical relations were also proposed for clear-water and live-bed scour separately.