avila sapienza-may2015

Research Seminar

SUZANA MOREIRA AVILAAssociate Professor

University of Brasilia – BrazilRome, May 29th 2015

Resumé

• 1993 - Civil Engineer – University of Brasilia

• 1997 – Master in Structural Engineering – University of Brasilia

• 2002 – Doctor in Structural Engineering - Pontifical Catholic Universityof Rio de Janeiro

• 2002-2008 – Associate researcher – University of Brasilia

• 2008 – now – Associate professor – University of Brasilia

Expertise

• Structural Dynamics

• Structural Control

• Structural Optimization

• Numerical Analysis and Computational Methods

Research Partner’s

Prof. Marcus Morais

Structural Dynamics

Computational Mechanics

Fluid structure Iteraction

Prof. Maura Shzu

Computational Mechanics

Structural Optimization

University of Brasilia

Darcy Ribeiro Campus

University of Brasilia

Gama Campus

Structural Control

• It is a technology to reduce excessive vibration in structures caused by dynamic loadings such as wind and earthquakes.

• Although it was developed first in aerospace engineering, this technology has fastly spread to Civil Engineering

Structural Control

• Structural control provide changes on stiffness and dampingproperties of the system, installing external devices or applyingexternal forces, aiming to reduce original structure vibrations.

• It can be classified as passive, active, semi-active and hybrid.

Footbridge in Brasilia

A gym floor, that presented real excessive vibrations, located in a commercial building situated in the city of Brasilia, Brazil

Tuned Mass Damper TMD

m

g(t)

k

cK

C

M

f(t)

Dynamic testing platform

• Situated at the Structure Laboratory there is a testing platform with a very low fundamental frequency and presenting excessive vibrations.

Dynamic testing platform

• Tuned mass damper.

Tuned mass damper to reduce floor vibration

Structural control of adjacent buildings

Numerical model of National Brasilia Stadium

Wind Turbines: model, control and optimize

Wind turbine tower

The tower is about 20% of the total cost!

Wind turbine tower dynamic analysis

Numerical modelling of the wind turbine tower

Numerical modelling of the wind turbine tower

Vibration control of the wind turbine tower

Kp,CpFs(t)

Ks

Cs

Ms

Mp

(t)

L

y(t)

0,20

0,40

0,60

0,80

1,00

1,20

1,40

1,60

1,80

0,8 0,9 1,0 1,1 1,2 1,3 1,4 1,5

a = wP / wS

RMS m=0, 06

m=0, 08

m=0, 10

Vibration control wind turbine

Floating Offshore Wind Turbine

Hywind, Norway

Offshore wind turbine model

Structural ControlTunned Mass Damper Inverted Pendulum

0 50 100 150 200 250 300-0.06

-0.04

-0.02

0

0.02

0.04

0.06Comparacao - Com AMS vs Sem AMS

Tempo [s]

Am

plitu

de d

e T

heta

[ra

d]

Sem AMS

Com AMS

Offshore wind turbine vibration control

Developing, Next steps, ideas, etc

• Optimization of tmd parameters

• Tower Optimization

• Blade effects

• Semi-active control

• Seismic analysis

• Vibration control of blades

Thanks for your attention!!