A Numerical Study on the Behavior of Offshore Suction Bucket Foundations under Cyclic Lateral Loading

2020-01-01
Alp, Yilmaz S.
Ercan, Tasan H.
Offshore wind turbines are exposed to high cyclic lateral loads induced by wind and waves which play a special role in the design of foundations. It's essential to clarify the bucket behavior under cyclic lateral loading to fulfil the design requirements of these foundations in both ultimate and serviceability limit states. In this study the behavior of monopods embedded in saturated sandy soil subjected to cyclic lateral loads were investigated using a sophisticated finite element model. The accumulation of permanent soil deformations and excess pore water pressure in saturated sandy soil due to cyclic lateral loading are taken into account by a fully coupled two-phase model combined with a hypoplastic constitutive model. Porosity-permeability dependence is modelled with the Kozeny-Carman relationship. The main focus was dedicated to loads levels that led to progressive failure, attenuation, and shakedown behavior under cyclic lateral loading. The main finding of these investigations are presented which make an effective contribution to the safe and economic design of bucket foundations.

Suggestions

A study on the behaviour of offshore suction bucket foundations under cyclic axial compressive loading
Yilmaz, S. Alp; TAŞAN, HACI ERCAN (2021-10-01)
Suction bucket foundations of offshore wind turbines (OWTs) are subjected to cyclic loads induced by wind and waves. The behaviour of buckets embedded in saturated sandy soil subjected to cyclic axial compression was studied using a finite element (FE) model. Accumulation of permanent soil deformations and excess pore water pressure in saturated sandy soil due to cyclic axial compression were taken into account by a fully coupled two-phase model combined with a hypoplastic constitutive model with intergranu...
A Numerical Study on the Behaviour of Suction Bucket Foundations for Offshore Wind Turbines under Cyclic Loading
Yılmaz, Seyit Alp; Bakır, Bahadır Sadık; Taşan, Hacı Ercan; Department of Civil Engineering (2021-5-24)
Suction bucket foundations simply consist of a cylinder skirt and a top plate, usually made of steel and installed by the assist of suction are a relatively new and economically favorable solution for offshore wind turbines which are exposed to high lateral loads from winds and waves both of which have cyclic characteristic. Understanding the behaviour under the effect of complex cyclic load environment is essential to assess the design requirements of bucket foundations. Deformations and pore pressures may...
An investigation of liquefaction effects on piers and piles of segmental precast balanced cantilever bridges
Gündüz, Özer; Caner, Alp; Department of Earthquake Studies (2019)
In this thesis, the seismic behavior of a typical segmental precast balanced cantilever bridge over liquefiable soils is investigated. Liquefaction is a phenomenon that is triggered by large movements of the sand layer during earthquakes and cause damage to structures. The subject is still under investigation, approaches for liquefaction induced lateral spreading calculations can be found in the literature. Inertial and kinematic effects of the lateral spreading were studied with a total of four different a...
Experimental Study of a TLP Offshore Floating Wind Turbine
Oğuz, Elif; Clelland, David; İncecik, Atilla; Dai, Saishuai; López, Juan Amate; Sánchez, Gustavo (null; 2016-07-18)
Tank testing in a wind and wave environment is a key part of the design process for the development of an offshore floating wind turbine. The current paper describes an extensive experiment campaign carried out at the Kelvin Hydrodynamics Laboratory at the University of Strathclyde to determine the hydrodynamic performance of the Iberdrola TLPWIND offshore floating wind turbine with the NREL 5MW reference turbine over a range of environmental conditions. Tests were carried out for 70m water depth and the de...
Investigation of the effect of bending twisting coupling on the loads in wind turbines with superelement blade definition
Gözcü, Mehmet Ozan; Kayran, Altan; Department of Aerospace Engineering (2014)
In this thesis study, the effect of off-axis plies in the spar caps of a wind turbine blade on the damage equivalent loads in a wind turbine system is investigated. The off-axis plies in the spar caps are exploited for load alleviation in the whole turbine system since the off-axis plies induced bending-twisting coupling into blades of wind turbine. Damage equivalent load is used to assess the effect of bend twist coupled blade on the fatigue load reduction in the whole wind turbine system. NREL's 5 MW turb...
Citation Formats
Y. S. Alp and T. H. Ercan, “A Numerical Study on the Behavior of Offshore Suction Bucket Foundations under Cyclic Lateral Loading,” 2020, p. 851, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/64852.