Effects of installation on the cyclic axial behaviour of suction buckets in sandy soils

Date

2019-10-01

Author

Taşan, Hacı Ercan
Yilmaz, S. Alp

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

221
views

0
downloads

Suction buckets differ with their easy and cost-efficient installation technique from other foundation types for offshore wind turbines. For successful completion of their installation process, suction is essential, but the imposed seepage leads to the changes in states of the soil in and around the bucket. Especially, a loosening of soil inside the bucket affects the load carrying behaviour of bucket subjected to repetitive loading resulting from environmental conditions. In this study, the behaviour of buckets under cyclic axial compressive loads with considering a possible loosening and related changes in permeability of soil inside the bucket is investigated numerically. In the framework of finite element analysis, a fully coupled two-phase model and a hypoplastic constitutive model are used to describe the saturated sandy soil behaviour under repetitive loading. The porosity-permeability variation is taken into account by Kozeny-Carman relationship. Special attention is dedicated to load carrying behaviour of bucket top plate, inner and outer skirt as well as base and their changes resulting from a loosening of soil inside the bucket with variable aspect ratio. For this purpose, cyclic axial compressive loads which cause an attenuation and progressive failure of soil-bucket system response are considered. The main findings on the changes in load carrying behaviour of bucket are presented and discussed.

Subject Keywords

Ocean Engineering

URI

https://hdl.handle.net/11511/51806

Journal

APPLIED OCEAN RESEARCH

DOI

https://doi.org/10.1016/j.apor.2019.101905

Collections

Graduate School of Natural and Applied Sciences, Article

Suggestions

OpenMETU
Core

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...
Experimental and numerical analysis of a TLP floating offshore wind turbine Oğuz, Elif; Day, Alexander H.; Incecik, Atilla; Amate Lopez, Juan; Sánchez, Gustavo; Gonzalez Almeria, Gonzalo (Elsevier BV, 2018-01-01) This paper describes an experimental and numerical investigation of the Iberdrola TLP wind turbine concept, TLPWINID, in realistic wind and wave conditions. The TLP was coupled to the NREL 5 MW reference turbine and was designed to operate in a water depth of 70 m. The test campaign included free oscillation tests, tests in regular and irregular waves and simulated wind conditions.
A Numerical Study on the Behavior of Offshore Suction Bucket Foundations under Cyclic Lateral Loading Alp, Yilmaz S.; Ercan, Tasan H. (2020-01-01) 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 o...
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...
Effect of Fiber Orientation of Bend-Twist Coupled Blades on the Structural Performance of the Wind Turbine System Şener, Özgün; Kayran, Altan (2017-01-05) The effect of fibre angle of bend-twist coupled mixed GFRP-CFRP wind turbine blades on the structural performance of the wind turbine system is studied. For the structural performance evaluation, the effect of the use of off-axis plies in the main spar caps of the bendtwist coupled wind turbine blade on the reduction of damage correspondent internal loads in the whole wind turbine system, electrical power produced, tower-blade end gap, and maximum stress in the blades are taken as major criteria. Different ...

Citation Formats

H. E. Taşan and S. A. Yilmaz, “Effects of installation on the cyclic axial behaviour of suction buckets in sandy soils,” APPLIED OCEAN RESEARCH, pp. 0–0, 2019, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/51806.