Evaluation of small-scale laterally loaded monopiles in sand

H. R. Roesen, K. Thomassen, S.P.H. Sørensen, L.B. Ibsen

In the proceedings of: GEO2011: 64th Canadian Geotechnical Conference, 14th Pan-American Conference on Soil Mechanics and Geotechnical Engineering, 5th Pan-American Conference on Teaching and Learning of Geotechnical Engineering

Session: Deep Foundations

ABSTRACT: In current designs of offshore wind turbines, monopiles are often used as foundation. The behaviour of the monopiles when subjected to lateral loading has not been fully investigated. In this paper the diameter effect on laterally loaded non-slender piles in sand is evaluated by means of results from six small-scale laboratory tests, numerical modelling of the same test setup and existing theory. From the numerical models, py curves are derived and compared to current design regulations. The recommendations in API (1993) and DNV (1992) are observed to be in poor agreement with the numerically obtained py curves. The initial stiffness, Epy*, of the py curves is found to increase with increasing pile diameter. Considerable uncertainties are observed to be related to small-scale testing, and the evaluations clearly indicate that the accuracy of small-scale testing is increased when increasing the pile diameter and applying overburden pressure. PRESENTACIONES TÉCNICAS En el actual diseño de turbinas eólicas marinas, mono-pilas son generalmente usadas como cimentación. El comportamiento de las mono-pilas sometidas a cargas laterales no ha sido completamente investigado. En este articulo, la influencia del diámetro en pilas no esbeltas sujetas a cargas laterales es evaluada a través de 6 test de laboratorio a pequeña escala, modelos numéricos de los propios test y el uso de la teoría existente. Del los modelos numéricos, las curvas p-y son obtenidas y comparadas con la actual normativa de diseño. Las recomendaciones de la API (1993) y DNV (1992) muestran una pobre similitud con las curvas p-y obtenidas de forma numérica. Se ha hallado que la rigidez inicial, Epy* de las curvas p-y incrementa con el incremento de diámetro de la pila. Además, se hallan incertidumbres considerables relacionadas con los test a pequeña escala, y la evaluación de los mismos indica claramente que la precisión de los test a pequeña escala se ve incrementa cuando el diámetro de la pila y la presión de sobrecarga son incrementadas.

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Cite this article:
H. R. Roesen; K. Thomassen; S.P.H. Sørensen; L.B. Ibsen (2011) Evaluation of small-scale laterally loaded monopiles in sand in GEO2011. Ottawa, Ontario: Canadian Geotechnical Society.

@article{GEO11Paper1098,author = H. R. Roesen; K. Thomassen; S.P.H. Sørensen; L.B. Ibsen ,title = Evaluation of small-scale laterally loaded monopiles in sand,year = 2011}