Scour below marine pipelines due to random waves on mild slopes

This paper provides a practical stochastic method by which the maximum equilibrium scour depth beneath a marine pipeline exposed to random waves on mild slopes can be derived. The approach is based on assuming the waves to be a stationary narrow-band random process, adopting the Battjes and Groenendijk (2000) wave height distribution for mild slopes including the effect of breaking waves, and using the empirical formulas for the scour depth on the horizontal seabed by Sumer and Fredsoe (1996). Results will be presented and discussed by varying the seabed slope and water depth. An approximate method is also proposed, and comparisons are made with the present stochastic method. Generally, it appears that the approximate method can replace the stochastic method.