Ever since the wind induced collapse of the Tacoma Narrows Bridge (US) in November 1940, wind has been considered a crucial factor in bridge design. In order to avoid such catastrophes engineers have tried to increase the structure damping for critical frequencies and bending modes. One example of a passive solution that decreases the effect the wind forces exerts on the bridge is to streamline the bridge deck.

This project proposes an innovative wind-induced vibration attenuation strategy based on active control of the bridge’s aerodynamic profile. An array of adjustable winglets is installed along both edges of the girder and their angular position is controlled as a function of the current dynamic state of the structure and/or the local wind field measurement. The characteristics of the interaction between the wind field and the underlying structure (nonlinear, spatially heterogeneous, time-variant and noisy) with the additional degrees of freedom introduced by the flap system result in complex mathematical models and associated control strategies. In order to validadte the mathematical models set up to describe the system a physical active bridge section model has been installed in the EPFL windtunnel. Current project work focuses on the development of analytical and numerical models of the system, in parallell of investigating linear control laws for stabilizing the bridge deck using the flaps.

Team and Collaborators

• Maria Boberg
• Albrecht Lindner
• Shravan Kumar Sajja
• Dr. Glauco Feltrin (Structural Engineering Research Laboratory, EMPA)

Sponsors and Research Period

Related Student Projects and Internships

DISAL-SP71: Tiago Morais, System Identification and Calibration of an Active Bridge Section Model
DISAL-SP43: Vincent Mazoyer, Control of Active Flap in Wind Tunnel
DISAL-SU21: Nicolò Valigi, Wind Profiling and Pressure Distribution for an Airfoil Model in a Wind Tunnel
DISAL-IP11: Maria Boberg, System Identification of Mechanical Parameters for a 2D Bridge Section Model
DISAL-PP4: Albrecht Lindner, SmartBridge: Towards Active, Energy-Efficient Distributed Mitigation of Wind Effects on Long-Span Bridges
DISAL-PP3: Shravan Sajja, Smartbridge Project: Modeling and Design of Wind Tunnel Tests

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