Large Deformation Finite-Element Analysis of Submarine Landslide Interaction with Embedded Pipelines
Publication: International Journal of Geomechanics
Volume 10, Issue 4
Abstract
Submarine landslides represent one of the most significant geohazards on the continental slope in respect of the risk they pose to infrastructure such as deep water pipelines. A numerical approach, based on the finite-element method but using remeshing, was established in this paper to simulate large flow deformation of debris from a landslide and to quantify the loads and displacements imposed on pipelines embedded in the seabed. A simple two-dimensional elastic perfectly plastic soil model with plane strain conditions was employed in this analysis. The pipeline was restrained by a set of springs so that the load on the pipeline built up to a stable value, representing the limiting load at which the debris flowed over the pipeline. A parametric study was undertaken by varying the pipeline embedment and the relative strengths of the debris and seabed. The analysis results show that the various combinations of soil strength and embedment depth lead to different debris-pipeline movement patterns and consequently lead to rather different magnitudes of the loads imposed on pipelines. The pipeline is subjected to the largest load (an equivalent pressure of 11.5 times debris strength) from the landslide when it rests on the weakest seabed. The pressure is proportional to the debris material strength but varies inversely with the seabed strength for partially embedded pipelines. For all strength combinations, there is a critical embedment depth beyond which the force on the pipeline reduces to a very small magnitude.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
This work forms part of the activities of the Centre for Offshore Foundation System at UWA, which was established under the Australian Research Council’s Special Research Centre scheme and is now supported by the State Government of Western Australia through the Centre of Excellence in Science and Innovation program. The research presented in the paper is part of a joint industry project administered and supported by the Minerals and Energy Research Institute of Western Australia, and by BP, BHP Billiton, Chevron, Petrobras, Shell, and Woodside. Additional funding was provided by the CSIRO Flagship Collaboration Cluster on Subsea Pipelines. The various support is gratefully acknowledged.
References
Angell, M., Hanson, K., Swan, B., and Youngs, R. (2003). “Probabilistic fault displacement hazard assessment for flowlines and export pipelines, Mad Dog and Atlantis field developments, deepwater Gulf of Mexico.” Proc., Offshore Technology Conf., Paper OTC 15202.
Bea, R. G., and Aurora, R. (1982). “Design of pipelines in mudslide areas.” Proc., Offshore Technology Conf., Paper OTC 4411.
Bruschi, R., Bughi, S., Spinazze, M., Torselletti, E., and Vitali, L. (2006). “Impact of debris flows and turbidity currents on seafloor structures.” Norwegian Journal of Geology, 86, 317–337.
Carter, J. P., and Balaam, N. P. (2006). AFENA user manual (6.0), Centre for Geotechnical Research, The Univ. of Sydney, Sydney, Australia.
Demars, K. R. (1978). “Design of marine pipelines for areas of unstable sediment.” Transp. Engrg. J., 104(1), 109–112.
Georgiadis, M. (1991). “Landslides drag forces on pipelines.” Soil Found., 31(1), 156–161.
Hu, Y., and Randolph, M. F. (1998a). “A practical numerical approach for large deformation problems in soil.” Int. J. Numer. Analyt. Meth. Geomech., 22(5), 327–350.
Hu, Y., and Randolph, M. F. (1998b). “Deep penetration of shallow foundations on non-homogeneous soil.” Soil Found., 38(1), 241–246.
Jeanjean, P., Liedtke, E., Clukey, E. C., Hampson, K., and Evans, T. (2005). “An operator’s perspective on offshore risk assessment and geotechnical design in geohazard-prone areas.” Proc., Int. Symp. on Frontiers in Offshore Geotechnics, Taylor & Francis, London, 115–143.
Jiang, L., and LeBlond, P. H. (1993). “Numerical modelling of an underwater Bingham plastic mudslide and the water wave which it generates.” J. Geophys. Res., 98, 10,303–10,317.
Lee, H. J., and Edwards, B. D. (1986). “Regional method to assess offshore slope stability.” J. Geotech. Engrg., 112(5), 489–509.
Lee, H. J., Schwab, W. C., Edwards, B. D., and Kayen, R. E. (1991). “Quantitative controls on submarine slope failure morphology.” Mar. Geotech., 10, 1–2.
Locat, J. (2001). “Instabilities along ocean margins: a geomorphological and geotechnical perspective.” Mar. Pet. Geol., 18(4), 503–512.
Locat, J., and Lee, H. J. (2002). “Submarine landslides: advances and challenges.” Can. Geotech. J., 39, 193–212.
Lu, Q., Hu, Y., and Randolph, M. F. (2000). “FE analysis for T-bar and spherical penetrometers in cohesive soil.” Proc., 10th Int. Offshore and Polar Engineering Conf., Vol. 2, International Society of Offshore and Polar Engineers (ISOPE), Cupertino, Calif., 617–623.
Lu, Q., Hu, Y., and Randolph, M. F. (2001). “Deep penetration in soft clay with strength increasing with depth.” Proc., 11th Int. Offshore and Polar Engineering Conf., International Society of Offshore and Polar Engineers (ISOPE), Cupertino, Calif., 785–794.
Nadim, F., Krunic, D., and Jeanjean, P. (2003). “Reliability method applied to slope stability problems: Estimating annual probabilities of failure.” Proc., Offshore Technology Conf., Paper OTC 15203.
Niedoroda, A. W., Reed, C. W., Hatchett, L., Young, A., Lanier, D., Kasch, V., Jeanjean, P., Orange, D., and Bryant, W. (2003). “Analysis of past and future debris flows and turbidity currents generated by slope failures along the Sigsbee Escarpment in the deep Gulf of Mexico.” Proc., Offshore Technology Conf., Paper OTC 15162.
O’Brien, J. S., and Julien, P. Y. (1988). “Laboratory analysis of mudflow properties.” J. Hydraul. Eng., 114(8), 877–887.
Randolph, M. F., and Houlsby, G. T. (1984). “The limiting pressure on a circular pile loaded laterally in cohesive soil.” Geotechnique, 34(4), 613–623.
Randolph, M. F., Martin, C. M., and Hu, Y. (2000). “Limiting resistance of a spherical penetrometer in cohesive material.” Geotechnique, 50(5), 573–582.
Shapery, R. A., and Dunlap, W. A. (1978). “Prediction of storm-induced sea-bottom movements and platform forces.” Proc. Offshore Technology Conf., Paper OTC 3259.
Swanson, R. C., and Jones, W. T. (1982). “Mudslide effect on offshore pipelines.” Transp. Engrg. J., 108(6), 585–600.
Zakeri, A., Hoeg, K., and Nadim, F. (2008a). “Submarine debris flow impact on pipeline: drag force, mitigation, and control.” Proc., Offshore Technology Conf., OTC 19173.
Zakeri, A., Hoeg, K., and Nadim, F. (2008b). “Submarine debris flow impact on pipelines-Part I: Experimental investigation.” Coastal Eng., 55, 1209–1218.
Zakeri, A., Hoeg, K., and Nadim, F. (2009). “Submarine debris flow impact on pipelines-Part II: Numerical analysis.” Coastal Eng., 56, 1–10.
Information & Authors
Information
Published In
Copyright
© 2010 ASCE.
History
Received: May 11, 2009
Accepted: Dec 2, 2009
Published online: Dec 4, 2009
Published in print: Aug 2010
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.