The design of marine outfall pipelines must take into account four structural factors: (1) installation stress, (2) stress induced by anchoring if applicable, (3) collapse/buckling analysis, and (4) unsupported pipe spans. Installation stress can be analyzed by calculating the estimated magnitude of forces acting on the pipeline induced by the selection construction method and equipment. For instance, if the pipeline is to be pulled into place, the maximum pulling force can be divided by the pipe wall thickness area to determine stress. Operational stresses are due to environmental factors such as slumping of deltaic soils, scouring of supporting sediments by wave or current action, or even flotation due to removal of overburden, all of which create supported lengths.
KeywordsVortex Trench Riser
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- 3.Bruschi, R., Simantiras, P., Vitali, L., and Jacobsen,V. 1994. Vortex shedding-induced oscillations on pipelines resting on uneven seabeds. predictions and counter-measures. Int. Conf. on Hydroelasticity in Marine Technology, Trondheim, Norway,: (also available in Italian).Google Scholar
- 4.Bruschi, R., et al. 1991 Free-spanning pipelines: a review. ISOPE Conference. Edinburgh.Google Scholar
- 5.Bryndum, M.B., Bonde, E., Smitt, L.W., Tura, F., and Montesi, M. 1989. Long free spans exposed to currents and waves: model tests. 21st Offshore Technology Conference, Houston.Google Scholar
- 6.Bryndum, M.B., Nielsen, K.G., and Jacobsen, V. Free-spanning pipelines. Lecture notes. Design and analysis of slender marine structures: risers and pipelines. WEHGEMT Graduate School. Trondheim.Google Scholar
- 7.Bryndum, M.B., Vested, H.J., Nielsen, K.G., and Gravesen, H. 1989. Improved design methods for spanning of pipelines. Offshore Pipe Technology, 1989 European Seminar.Google Scholar
- 8.Jacobsen, V.J., Bryndum, M.B., Nielsen, RF., and Fines, S. 1984. Crossflow vibrations of a pipe close to a rigid boundary. J. Energy Resources Technology, Dec. 1984, v. 108.Google Scholar
- 9.Reynolds, J.M. 1981. Design and construction of sea outfalls. Chapter 13, Coastal Discharges. Thomas Telford, Ltd. London. 119–126.Google Scholar
- 10.Rolf, Th. von, and Ruback, H. 1924. The frequency of the eddies generated by the motion of circular cylinders through a fluid. British Advisory Committee for Aeronautics, R. & M. 917. Summarized in Ref (3).Google Scholar
- 11.Steinman, D.B. 1946. Problems of aerodynamic and hydrodynamic stability. Proc., 3rd Hydraulics Conference. Studies in Engineering, Bull. No. 31, University of Iowa, Iowa City.Google Scholar
- 12.Tura, F., Dminrescu, A., Bryndum, M.B., and Smed, P.F. 1944. OMAE 1994, Houston, Vol. V, 247–256.Google Scholar
- 13.Tsahalis, D.T. 1984. Vortex-induced vibrations of a flexible cylinder near a plane boundary exposed to steady and wave-induced currents. Proc. 3id OMAE Conference, New Orleans.Google Scholar