The Preliminary Study of Dynamic Responses of Offshore Wind Turbine Foundations

Abstract

Not like the steady environment of European wind farms in order to overcome disasters such as typhoon and earthquake the construction of Taiwanese offshore wind turbines requires rigorous and complete analyses of foundation dynamic responses The objective of this paper is to modularize the calculation of pile stiffness and damping in all degrees of freedom (i e vertical sliding rocking coupling or torsional vibration) using DynaN v3 0 and DynaPile v2016 One is based on the Improved Novak’s Method which a non-reflective boundary is introduced to obtain a more realistic model that accounts for non-linear effects; the other one is based on the Consistent Boundary Method including the techniques of Soil-Structure Interaction and transfer functions that are related to the computation of kinematic responses excited by seismic loading Following is the parametric study conducted by several models with variation of soil profiles pile rigidity slenderness boundary conditions and different layouts for pile groups Once the modeling of dynamic behavior as well as group effect of piles meets the results determined by other experiments or numerical researches on frequency domain both the charts and tables produced by programs are confirmed Besides the case study is necessary Considering a 3 6 MW wind turbine located on Fuhai offshore windfarm Changhua City the simplified model set according to design data and borehole reports has been analyzed Dynamic responses due to periodic wave load or real seismic events could be estimated by programs instead of in-situ measurements and provide the information for improvement of wind turbine foundations more accessible

Date of Award	2019
Original language	English
Supervisor	Sheng-Huoo Ni (Supervisor)