Banca de DEFESA: ROBSON RIBEIRO

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : ROBSON RIBEIRO
DATE: 26/06/2020
TIME: 14:00
LOCAL: Videoconferência
TITLE:

NON-LINEAR SOIL-STRUCTURE INTERACTION OF A PILED RAFT WIND TURBINE FOUNDATION: EFFECTS ON THE MODAL AND DYNAMIC ANALYSIS ON A NREL 5 MW WIND TURBINE

KEY WORDS:

Wind turbine foundations; piled raft; Modal analysis; Dynamic Analysis; Soilstructure interaction; ABAQUS; NREL 5M.

PAGES: 202
BIG AREA: Engenharias
AREA: Engenharia Civil
SUMMARY:

Wind turbine support structures are dynamically sensible structures. With the rotor diameter rise, in order to increase energy production, this situation tends to get more critical, giving rise to the needing of more accurate studies regarding system’s dynamic behaviour. It is known that, due to previous researches and design practice, soil-structure interaction plays a major role in the wind turbine natural frequencies of vibration, as well as in the stresses and displacements when applying dynamic operational and wind loads. Considering this scenario, the present research seeks to study non-linear soil-structure interaction models for analysing wind turbine towers. It was used a wind turbine model from National Research Laboratory (NREL) with nominal power of 5 MW and geotechnical data of Wind Power Plant Miassaba 3, located in the Rio Grande do Norte State. Four different SSI models were used: an analytic model with the expressions from DNV (2002); non-linear numerical FEM model (ABAQUS) using p-y, t-z and Q-z load transfer curves from API (2005); non-linear numerical FEM model (ABAQUS) calibrated with pile load test from Miassaba’s construction site; non-linear FEM model (ABAQUS) with elasto-plastic constitutive model (Mohr-Coulomb failure criteria) also calibrated with the same pile load tests. The results shows a discrepancy between analytical and numerical models, where the former provides larger values of global foundation stiffness, the differences being more critical for extreme load case scenarios. This fact brings attention towards to the needing of non-linear models for the dynamic behaviour assessment, in order to have more reliable foundation design. Additionally, the effects of SSI were evaluated in term of dynamic amplificatory factor of 1P load, which revealed a 16% and 20% foundation load increasing, respectively, in overturning moment and horizontal force.

BANKING MEMBERS:
Interno - 1752508 - DANIEL NELSON MACIEL
Presidente - 1515200 - JOSE NERES DA SILVA FILHO
Externo à Instituição - LUIZ CARLOS DE ALMEIDA - UNICAMP