Performance of Bucket Foundation Resting on Sand Subjected To Vertical Load

Document Type : Research Article


Civil Engineering faculty, Semnan University


 In comparison with the monopile foundation, bucket foundation is an economical option to reduce the construction costs of offshore wind turbines. It is similar to a suction caisson, which is driven into the soil like an upside-down bucket. Various available scientific researches have stated that how the length of skirt affects the ultimate capacity (qult) of bucket foundations that are utilized for different kinds of offshore applications. The experiments and 3D FE analyses have been performed to assess the ultimate vertical load capacity (Vult) of bucket foundations. The experiments were conducted on loose sand and it shows that as the length of the skirt increases, the qult enhances. A conceptual relationship as a depth factor was suggested to estimate the Vult of bucket foundations on the sand with regard to embedment ratio and soil friction angle. The FE analysis results have shown that the inner soil in the bucket foundation approximately behaves as a rigid body under the vertical loading. Therefore, it might be supposed that with similar dimension, the qult of embedded and bucket foundation is close. Moreover, it was found that due to the increase in the slip line length of bucket foundation, the foundation failed in greater settlement than surface footing.


Main Subjects

[1]M. F. Randolph and S. Gourvenec, Offshore geotechnical engineering. Spon press, 2011.
[2] G. Houlsby and B. Byrne, “Suction caisson foundations for offshore wind turbines,” Wind Eng., vol. 24, no. 4, pp. 249–255, 2000.
[3] S. A. Ibsen, L. B.; Schakenda, B.; Nielsen, “Development of the bucket foundation for offshore wind turbines, a novel principle,” in Gigawind-Sym. Offshore-Windenergie, Bau- und umwelttechnische Aspekte, Hannover., 2004.
[4] T. I. Tjelta, “The suction foundation technology,” in Frontiers in Offshore Geotechnics III – Meyer (Ed.) © 2015 Taylor & Francis Group, London, ISBN: 978- 1-138-02848-7, 2015.
[5] G. T. Houlsby, L. B. Ibsen, and B. W. Byrne, “Suction caissons for wind turbines,” in International symposium on Frontiers in Offshore Geotechnics, 2005, pp. 75–94.
[6] ISO:19901-4, “Petroleum and natural gas industries—Specific requirements for offshore structures—Part 4: Geotechnical and foundation design considerations,” 2003.
[7]    Det Norske Veritas (DNV), “Classification notes No. 30.4, Foundations,” 1992.
[8]  API, “Recommended Practice for Planning , Designing and Constructing Fixed Offshore Platforms — Working Stress Design,” 2000.
[9] A. Barari and L. B. Ibsen, “Undrained response of bucket foundations to moment loading,” Appl. Ocean Res., vol. 36, pp. 12–21, 2012.
[10] K. Terzaghi, Theoretical soil mechanics. New York: John Wiley & Sons, 1943.
[11] C. M. Martin, “Physical and numerical modelling of offshore foundations under combined loads,” University of Oxford. p. 306, 1994.
[12] M. J. Cassidy, B. W. Byrne, and G. T. Houlsby, “Modelling the behaviour  of  circular  footings  under combined loading on loose carbonate sand,” G-otechnique, vol. 52, no. 10, pp. 705–712, 2004.
[13] L. B. Ibsen, K. A. Larsen, and A. Barari, “Calibration of failure criteria for bucket foundations on drained sand under general loading,” J. Geotech. Geoenvironmental Eng., vol. 140, no. 7, pp. 1–16, 2014.
[14] F. Bransby and M. Randolph, “The effect of embedment depth on the undrained response of skirted foundations to combined loading,” Geotechnique, vol. 45, no. 5, pp. 637–655, 1999.
[15] S. Gourvenec, “Effect of embedment on the undrained capacity of shallow foundations under general loading,” Geotechnique, vol. 58, no. 3, pp. 177–185, 2008.
[16] L. B. Ibsen, a. Barari, and K. a. Larsen, “Modified vertical bearing capacity for circular foundations in sand using reduced friction angle,” Ocean Eng., vol. 47, pp. 1–6, 2012.
[17] J.-S. Park, D. Park, and J.-K. Yoo, “Vertical bearing capacity of bucket foundations in sand,” Ocean Eng., vol. 121, no. 1, pp. 453–461, 2016.
[18] F. A. Villalobos, “Model testing  of  foundations  for offshore wind turbines,” Ph.D. thesis, Oxford University, 2006.
[19] M. Y. Al-Aghbari and R. K. Dutta, “Performance of square footing with structural skirt resting on sand,” Geomech. Geoengin., vol. 3, no. 4, pp. 271–277, Dec. 2008.
[20] H. T. Eid, “Bearing Capacity and Settlement of Skirted Shallow Foundations on Sand,” Int. J. Geomech., vol. 13, no. 5, pp. 645–652, 2013.
[21] A. Barari, L. B. Ibsen, A. Taghavi Ghalesari, and K. A. Larsen, “Embedment Effects on Vertical Bearing Capacity of Offshore Bucket Foundations on Cohesionless Soil,” Int. J. Geomech., vol. 17, no. 4, p. 04016110, Apr. 2017.
[22] B. W. Byrne and G. T. Houlsby, “Drained behaviour of suction caisson foundations on very dense sand,” in Proc., Offshore Technology Conf., Offshore Technology Conference, Houston, 10994, 1999.
[23] A. Cerato and A. Lutenegger, “Published_JGGE_ Scale_Effects.pdf,” J. Geotech. Geoenvironmental Eng., vol. 133, no. 10, pp. 1192–1201, 2007.
[24] S. Paikowsky, M. Canniff, K. Lesny, A. Kisse, S. Amatya, and R. Muganga, LRFD Design and Construction of Shallow Foundations for Highway Bridge Structures, NCHRP Report 651. Washington, DC: Transportation Research Board, 2010.
[25] R. Lagioia, A. Sanzeni, and F. Colleselli, “Air, water and vacuum pluviation of sand specimens for the triaxial apparatus,” Soils Found., vol. 46, no. 1, pp. 61–67, 2006.
[26] F. M. Wood, J. A. Yamamuro, and P. V. Lade, “Effect of depositional method on the undrained response of silty sand,” Can. Geotech. J., vol. 45, no. 11, pp. 1525–1537, Nov. 2008.
[27] A.  Haddad,  R.  Amini,  and  A.  Barari,  “Effect   of embedment on the vertical capacity of bucket foundation in loose saturated sand: Physical modeling,” Mar. Georesources Geotechnol., vol. 0, pp. 1–9, 2018.
[28] B. Look, Handbook of Geotechnical Investigation and Design Tables, vol. 53, no. 9. 2013.
[29] D. Loukidis and  R.  Salgado,  “Bearing  capacity  of strip and circular footings in sand using finite elements,” Comput. Geotech., vol. 36, no. 5, pp. 871– 879, 2009.
[30] E. Diaz-Segura, “Assessment of the range of variation of N from 60 estimation methods for footings on sand,” Can. Geotech. J., vol. 800, no. November 2012, pp. 793–800, 2013.
[31] M. Achmus, C. T. Akdag, and K. Thieken, “Load- bearing behavior of suction bucket foundations in sand,” Appl. Ocean Res., vol. 43, pp. 157–165, 2013.
[32] C. M. Martin, “Exact bearing capacity calculations using the method  of  characteristics,”  in  11th  of  the  Proceedings  of  the  International  Conference  on Analytical and Computational Methods in Geomechanics, Turin, 2005, pp. 441–450.
[33] M. Lyamin, A., Salgado, R., Sloan, S.W., and Prezzi, “Two- and three-dimensional bearing capacity of footings in sand,” G-otechnique, vol. 57, no. 8, pp. 647–662, Jan. 2007.
[34] G. Yun and M. F. Bransby, “The undrained vertical bearing capacity of skirted foundations,” Soils Found., vol. 47, no. 3, pp. 493–505, 2007.