Boundary Element Analysis of Non-Linear Wave Forces on Buried Pipelines
In water depths up to 61m offshore pipelines are buried in excavated trenches to minimize their impact on the local environment and to reduce the possibility of accidental damage. For many practical reasons it is not unusual to have several pipelines buried in very close proximity to one another. A two-dimensional boundary element method which can be used to predict the seabed pressure field and the surface wave induced forces on a single buried pipe or any cluster configuration is presented. Of particular interest for design practice is the introduction of non-linear stream function wave theory into the formulation. A comparison of the boundary element model predictions with the analytical solution for a single buried pipeline, and a finite element model, which was validated using small scale laboratory tests is presented and discussed. The use of linear and non-linear ocean surface wave theories is examined and predictions of wave induced forces on several cluster configurations is presented. The two-dimensional boundary element approach is shown to be efficient and very suitable for this type of offshore application.
KeywordsPermeability Porosity Trench Crest Burial
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- 1.Brebbia, C. (1978). The Boundary Element Method for Engineers, Halsted Press, John Wiley & Sons, Inc., New York.Google Scholar
- 2.Brown, R.J. (1971). ”Rational Design of Submarine Pipelines,” World Dredging & Marine Construction, pp. 17-22.Google Scholar
- 3.Dean, R.G. (1974). Evaluation And Development of Water Wave Theories For Engineering Applications, CERC Special Rpt No. 1, Vol. I & II, U.S. Corps of Engineers.Google Scholar
- 4.Herbich, J.B., (1981). Offshore Pipeline Design Elements, Marcel Decker, Inc., New York.Google Scholar
- 5.Lai, N.W., Dominguez, R.F. and Dunlap W.A. (1974). ”Numerical Solutions for Determining Wave-Induced Pressure Distributions Around Buried Pipelines,” Sea Grant Report, TAMU-SG-75-205, pp.92.Google Scholar
- 7.Liu, P.L.F. and O’Donnell, T. (1983). “Wave-Induced Forces on Buried Pipelines in Permeable Seabeds,” ASCE Civil Engineering in the Oceans, pp. 111-121.Google Scholar
- 8.Liu, P.L.F. (1973). ”Damping of Water Waves over Porous Bed,” ASCE Journal of the Hydraulics Division, Vol. 99, HY 12, pp. 2263–2271.Google Scholar
- 9.MacPherson, H. (1978). “Wave Forces on Pipeline Buried in Permeable Seabed” ASCE Journal of the Waterway, Port, Coastal and Ocean Division, Vol. 104, WW4, pp. 407–419.Google Scholar
- 12.Sleath, J.F.A. (1970). “Wave-Induced Pressure in Beds of Sand”, ASCE Journal of the Hydraulics Division, Vol. 96, HY 2, pp. 367–378.Google Scholar