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Structural control has been comprehensively studied over the world as a multidisciplinary research field. The present work is motivated by an attempt to give a common frame to the recent research and applications of structural control technology in civil engineering across Europe. They include novel passive dampers, functional materials and semi-active dampers, active control systems, and their performance investigations. Design methods for the vibrations reduction of buildings, bridges, and wind turbines are discussed with reference to case studies. Control algorithms and dimension reduction techniques are also studied. Adaptation strategies and techniques based on the potential offered by piezoelectricity are reviewed

A highway bridge benchmark problem, focused on limiting excessive displacements during a given set of seismic events, has been formulated recently. The contribution summarized in this paper presents the application of a shape memory alloy (SMA) device to this benchmark problem. The analytical model of the SMA device is incorporated in the control force equation of the sample passive device. The effects of the proposed passive device on the dynamic response of the highway bridge are studied for six ground motion excitations. The results show that the proposed passive SMA damper can aggressively limit peak bearing and displacement response quantities during strong earthquakes. However, this is achieved at the cost of an increase in peak base shear and overturning moment. Such increase can be reduced by an integrated design of the device with other components of the bridge.

The use of shape memory alloy (SMA) components in passive structural control devices was repeatedly proposed in the last decade by several research groups. Among these proposals, an efficient coupling of SMA bars with a sliding system was recently introduced by the authors. It was studied at a prototype level to implement a base isolator with displacement limitations. This paper addresses first the issue of an accurate quality control on the alloy. Indeed an undesired creep effect has been experimentally detected in some specimens: it should be systematically avoided in passive control applications. The further step covers the transition from the prototype results to an accurate modelling of the device. Copyright © 2009 John Wiley & Sons, Ltd.

A new and innovative base isolation device is introduced in this paper based on extensive research carried out by the authors and their co-workers. A prototype of the device was built and experimentally tested on the shaking table. The new base isolation device consists of two disks, one vertical cylinder with an upper enlargement sustained by three horizontal cantilevers, and at least three inclined shape memory alloy (SMA) bars. The role of the SMA bars is to limit the relative motion between the base and the superstructure, to dissipate energy by their super-elastic constitutive law and to guarantee the re-centring of the device. To verify the expected performance, a prototype was built and tested under sinusoidal waves of displacement of increasing frequency with different amplitudes. It is shown that the main feature of the proposed base isolation device is that for cyclic loading, the super-elastic behavior of the alloy results in wide load-displacement loops, where a large amount of energy is dissipated.