Antonio Bonati

Effects of Environmental Conditioning on the Bond Behavior of FRP and FRCM Systems Applied to Concrete Elements

AbstractThis paper presents the results of an extensive experimental campaign of bond tests aimed to assess and compare the influence of several environmental conditioning factors (humidity and tem...

Experimental Assessment of a Skyhook Semiactive Strategy for Seismic Vibration Control of a Steel Structure

Sky-hook damping is one of the most promising techniques for feedback control of structural vibrations. It is based on the idea of connecting the structure to an ideal fixed point of the space through passive dissipative devices. Herein the benefit of semiactive (SA) sky-hook (SH) damping is investigated for seismic protection of a two-storey steel frame via shaking table tests. This kind of SA control is achieved implementing a continuous monitoring of selected structural response parameters and using variable dampers. The damping properties of the latter are changed in real-time so as to make the force provided by the damper match the desired SH damping force as closely as possible. To this aim, two prototype magnetorheological dampers have been installed at the first level of the frame and remotely driven by a SH controller. The effectiveness of the control strategy is measured as response to reduction in terms of floor accelerations and interstory drift in respect to the uncontrolled configuration. Two different calibrations of the SH controller have been tested. The experimental results are deeply discussed in order to identify the optimal one and understand the motivations of its better performance.

Laminated Glass Cantilevered Plates under Static and Impact Loading

The structural performance of cantilevered laminated glass plates for different glass thicknesses and interlayers is considered in this paper. Heat-strengthened and tempered glass plies and two different interlayer films were utilized. The response of laminated glass specimens is then evaluated under low-velocity hard and semirigid impacts. Experimental findings were simulated and discussed by means of finite element analyses. In particular, this discussion includes the evaluation of the influence that the fixed edge clamping technique (number of clamps, their size, and their stiffness) has on the stress distribution in the specimens.

DISSIPATING EFFECT OF GLAZED CURTAIN WALL STICK SYSTEM INSTALLED ON HIGH-RISE MEGA-BRACED FRAME-CORE BUILDINGS UNDER NONLINEAR SEISMIC EXCITATION

The results derived from the investigation on the dynamic behavior of glazed curtain wall non-structural stick systems installed in modern high-rise mega-frame prototypes is herein summarized. The supporting steel structures, designed in accordance with European rules, consisted of planar frames extracted from reference three-dimensional steel Moment Resisting Frame (MRF), respectively having thirtyand sixty-storey height. To limit interstorey drift and second order effects, outriggers trusses were placed every fifteen stories, whilst a CBF system was chosen as internal core. The characterization of non-structural façade elements was performed through experimental full-scale crescendo-tests on aluminium/glass curtain wall units. Deriving experimental force-displacement curves, it was possible to calibrate threedimensional inelastic FE models, capable to simulate the interaction between glass panels and aluminium frame. Subsequently, equivalent nonlinear links were calibrated to reproduce the dynamic behaviour of tested glazed unit, and implemented in the thirtyand sixty-storey structural planar frames FE models. Nonlinear time history analyses (NLTHAs) were performed to quantify local and global performance, investigating the enhanced combination of stiffness and strength generated through the implementation of glazed curtain wall on the numerical FE models. Results will be shown in terms of inter-storey drift profiles and displacement peaks, axial force curves and percentage peak variation, showing the sensitivity to the structure height. Trends were discussed to show that, if accurately designed, omitting non-structural elements from the seismic assessment of high-rise prototypes conduct to a sensible underestimation of dynamic dissipation capacity of the building. 3711 Available online at www.eccomasproceedia.org Eccomas Proceedia COMPDYN (2017) 3711-3727

Reliability of CFRP Structural Repair for Reinforced Concrete Elements

This paper presents the outcomes of load tests performed on concrete beams reinforced to withstand bending stress through the application of a carbon fibres-based compound. The innovative nature of the proposed experiment lies in the choice of reinforced elements, that is artificially deteriorated concrete beams.