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This work designs, models, and experimentally validates novel magnetic levitation systems for the vibration isolation of lightweight structures and artworks. 2D and 3D passive vibration isolators are studied, making use of easy‐to‐assemble 3D‐printed components and neodymium magnets. An optimized design of the number of magnets and the 3D printing process of the stabilizing parts allows us to finely tune the resonant frequencies and the vibration isolation performances. Ratios between the maximum horizontal and vertical accelerations, exhibited by the floating bodies, and the maximum horizontal acceleration applied to the base of the system are provided, for varying excitation frequencies. With these outputs, we show that it is possible to optimize the main design parameters of the isolation system, by targeting the desired frequency window, for a given payload. [ABSTRACT FROM AUTHOR]

Summary: Glass facades and enclosures are highly attractive structures with increasing popularity between architects and engineers. These structures show very specific design requirements so as to guarantee an efficient interaction with the other building components. This is especially true in the case of "adaptive" glass systems, with continuously changing configurations according to a given design criteria. The main goal of this explorative study is the design of an adaptive facade module with antagonistic actuation. The geometry of the glazing system is controlled by pairs of superelastic cables actuated against each other in a reversible way. Superelasticity is here exploited so as to improve the structural behavior of the facade system subjected to wind loads. The efficiency of the proposed design concept is demonstrated via finite‐element numerical analyses and also from test data obtained from an experimental prototype. It is shown that the proposed control approach can yield substantial structural enhancements and benefits for the adaptive facade module, which are substantiated by important reductions of maximum deformations and stresses in the cladding elements. [ABSTRACT FROM AUTHOR]

The present paper studies the feasibility, through physical experimentation, of efficient and low-cost macrostrain sensors, based on shape-memory alloy technologies. The motivation of this work is to explore the intrinsic relation between electrical resistivity and strain, associated with the development of the stress induced martensitic transformation in superelastic shape-memory alloys. This property enables the material to endure deformations up to 8% without any residual strains, making shape-memory alloy wires excellent candidates for kernel elements in innovative strain transducers with dynamic ranges 4 to 5 times larger than the currently available strain transducers. An experimental prototype of a beam with a set of SMA macrostrain sensors is presented, featuring a timed scanning sequential algorithm to successfully perform the resistance readings. The aim of this work is to provide an additional insight into the potential of SMAs in new macrostrain measurement applications. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Summary: The present paper provides an innovative insight into the design of column–base connections, for steel moment resisting frames, with superelastic shape‐memory alloy cables. The proposed strategy is to prevent damage in these connections due to the rotation demands associated with seismic events, by using lateral restraining cables working in phase opposition. A simplified experimental prototype of the proposed connection is tested, under several loading scenarios, proving to be a versatile solution in terms of rotational stiffness, with significant energy dissipating features and re‐centering capabilities. A series of numerical simulations are also performed, providing a clear evidence of the good seismic performance of the proposed superelastic connection in real‐scale civil engineering structures. [ABSTRACT FROM AUTHOR]