Cyclic behavior of unit bucket for tripod foundation system supporting offshore wind turbine via model tests

In current practice, the most common foundation type for Offshore Wind Turbine generators (OWT’s) at moderate water depths is the monopile. A model pile in scale 1:20 of a typical monopile foundation for offshore wind turbine has undergone lateral vibration testing in dry laboratory sand. Eigen-frequencies are determined based on acceleration measurements. The aim of the tests is to provide benchmark results for validation of different calculation methods for offshore wind monopile foundations. The stiffness contribution from the sand is evaluated on behalf of measuring the first natural frequency of the pile-soil interaction system. Preliminary results from back-calculations of the model tests using both 3D -FEM and a simple beam on elastic foundation model indicate that strain-dependent soil stiffness plays an important role for determining the system stiffness. In this paper, the model tests and their results are presented, along with the preliminary results from the back-calculation.

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Decision letter for "Studies on cyclic behavior of tripod suction bucket foundation system supporting offshore wind turbine using centrifuge model test"

10.1002/we.2586/v1/decision1 ◽

2020 ◽

Keyword(s):

Wind Turbine ◽

Model Test ◽

Offshore Wind ◽

Cyclic Behavior ◽

Offshore Wind Turbine ◽

Centrifuge Model Test ◽

Bucket Foundation ◽

Centrifuge Model

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A Simulation of Non-Simultaneous Ice Crushing Force for Wind Turbine Towers with Large Slopes

Energies ◽

10.3390/en12132608 ◽

2019 ◽

Vol 12 (13) ◽

pp. 2608 ◽

Cited By ~ 2

Author(s):

Li Zhou ◽

Shifeng Ding ◽

Ming Song ◽

Junliang Gao ◽

Wei Shi

Keyword(s):

Numerical Model ◽

Wind Turbine ◽

Ice Sheet ◽

Model Tests ◽

Offshore Wind ◽

Offshore Wind Turbine ◽

Foundation Design ◽

Cold Regions ◽

Crushing Force ◽

Ice Loads

When the offshore wind energy industry attempts to develop in cold regions, ice load becomes the main technological challenge for offshore wind turbine foundation design. Dynamic ice loads acting on wind turbine foundations should be calculated in a reasonable way. The scope of this study is to present a numerical model that considers the non-simultaneous ice crushing failure acting on the vertical structure of a wind turbine’s foundation. The local ice crushing force at the contact surface between the ice sheet and structure is calculated. The boundary of the ice sheet is updated at each time step based on the indentation length of the ice sheet according to its structure. Ice loads are validated against two model tests with three different structure models developed by other researchers. The time series of the ice forces derived from the simulation and model tests are compared. The proposed numerical model can capture the main trends of ice–wind turbine foundation interaction. The simulation results agree well with measured data from the model tests in terms of maximum ice force, which is a key factor for wind turbine design. The proposed model will be helpful for assisting the initial design of wind turbine foundations in cold regions.

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Studies on cyclic behavior of tripod suction bucket foundation system supporting offshore wind turbine using centrifuge model test

Wind Energy ◽

10.1002/we.2586 ◽

2020 ◽

Author(s):

Yeong‐Hoon Jeong ◽

Kil‐Wan Ko ◽

Dong‐Soo Kim ◽

Jae‐Hyun Kim

Keyword(s):

Wind Turbine ◽

Model Test ◽

Offshore Wind ◽

Cyclic Behavior ◽

Offshore Wind Turbine ◽

Centrifuge Model Test ◽

Bucket Foundation ◽

Centrifuge Model

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