Experimental Investigation on Specifications of Scouring Hole Under the Pipelines Across the Waterway Under Steady Flow

Document Type : Research Paper

Authors

1 M.Sc. in Civil Engineering, Water & Hydraulic Structures, Shahid Chamran University of Ahvaz, Ahvaz, Iran.

2 Professor, Department of Water Structures, Shahid Chamran University of Ahvaz, Ahvaz, Iran.

3 Assistant Professor, Department of Water Structures, Shahid Chamran University of Ahvaz, Ahvaz, Iran

Abstract

Pipelines passing across the river to convey water, gas, and petroleum may develop local scour at the pipeline location. Scour development may cause damage due to pipe failure and disorder in utilization. The eddy currents around the pipe lead to the scouring phenomenon causing the non-uniformity of the pipeline and its fracture which will ultimately have environmental and destructive consequences. In this study, the effect of pipe diameter has been investigated. The experiments were conducted with five diameters (20, 30, 40, 50, and 60 mm) in three Froude numbers (0.2, 0.235, and 0.26) under identical bed conditions. In the following part, scouring profiles were taken and the scouring progresses over time and maximum scour depth were investigated. The results show that scouring under pipe for a diameter of 60 mm has the highest and is the most progressing towards time compared to other diameters.

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Volume 43, Issue 3
October 2020
Pages 117-131
  • Receive Date: 22 May 2018
  • Revise Date: 28 November 2018
  • Accept Date: 02 December 2018
  • Publish Date: 22 September 2020