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Amarante dos Santos, Filipe, and Corneliu Cismaşiu. "Adaptive underslung beam using shape-memory alloys for frequency-tuning." Journal of Intelligent Material Systems and Structures (2016). AbstractWebsite

The present article addresses the study of an adaptive-passive beam structure with a shape-memory alloy based actuator. In order to mitigate adverse dynamic effects resulting from externally induced vibrations, the structure is able to automatically tune its natural frequency to avoid resonance. The adaptive-passive beam configuration is based on an underslung cable-stayed girder concept. Its frequency tuning is achieved by temperature modulation of the shape-memory alloy elements through a closed-loop control process based on a proportional-integral-derivative algorithm. The effectiveness of the proposed control solution is substantiated by numerical simulations and experimental tests on a small-scale prototype. The validated numerical model enables the simulation of the proposed control approach in a real-scale footbridge, subjected to a prescribed pedestrian loading. The results are very encouraging and show that, by activating the shape-memory alloy elements, the system is able to successfully shift its natural frequency and to mitigate the effects of induced vibrations.

Amarante dos Santos, Filipe, Corneliu Cismasiu, and Chiara Bedon. "Smart glazed cable façade subjected to a blast loading." Proceedings of the Institution of Civil Engineers-Structures and Buildings (2015): 1-10. Abstract

This paper investigates the dynamic behaviour of cable-supported glazing façades
subjected to medium-level air blast loads. Preliminary numerical studies are carried-out in
SAP2000 by means of a geometrically refined and simplified lumped-mass finite-element
numerical model, in order to assess the major effects of the design blast load in the main
façade components. As shown, both the glass panels and the cable system are able to
properly accommodate the incoming impulsive loads, typically involving extreme ...

and Amarante dos Santos, F. P. and Cismaşiu, Pamies Teixeira C. J. "Semi-active vibration control device based on superelastic NiTi wires." Structural Control and Health Monitoring. 20 (2013): 890-902.Website
Amarante dos Santos, Filipe, Corneliu Cismasiu, and Chiara Bedon. "Smart glazed cable facade subjected to a blast loading." Proceedings of the Institution of Civil Engineers - Structures and Buildings. 3.169 (2016): 223-232.
Amarante dos Santos, Filipe, Corneliu Cismasiu, and Francisco Braz Fernandes. "Cyclic Instability of Shape-Memory Alloys in Seismic Isolation Systems." International Journal of Structural Glass and Advanced Materials Research (2018): 1-14.
Bedon, Chiara, Filipe Santos, Claudio Amadio, and Corneliu Cismasiu. "Passive and active control systems for adaptive glazing systems and envelopes." European COST Action TU1403 "Adaptive facades network" Industry Workshop. Delft, The Netherlands 2015.
Bernardo, Vasco, André Oliveira, Filipe Amarante dos Santos, and Corneliu Cismasiu Vulnerabilidade e reforço sísmico de uma passagem superior pedonal pré-fabricada. 5as Jornadas Portuguesas de Engenharia de Estruturas. Lisboa, 2014.artigo_jpee2014.pdf
Buru, Stefan Marius, Válter Lúcio, and Corneliu Cismasiu. "PROTEDES - Protection of Strategic Buildings Against Blast - Final Report." PROTEDES2022. Região Sul da Ordem dos Engenheiros, Lisboa 2022.
Campian, C., M. Pop, C. Cismasiu, T. Josza, and A. Popa. "Seismic retrofitting of an existing steel structure." 17th International Multidisciplinary Scientific GeoConference SGEM 2017. Albena; Bulgaria 2017.
Cismasiu, C., J. R. G. Ferreira, and H. B. Rebelo. "Modelação tridimensional de ondas de choque em LS-DYNA." Construção Magazine.86 (2018): 24-28.
Cismasiu, Corneliu, and Filipe Amarante P. dos Santos. "Numerical simulation of superelastic shape memory alloys subjected to dynamic loads." Smart Materials and Structures. 17 (2008): 025036 (12pp). AbstractWebsite

Superelasticity, a unique property of shape memory alloys (SMAs), allows the material to recover after withstanding large deformations. This recovery takes place without any residual strains, while dissipating a considerable amount of energy. This property makes SMAs particularly suitable for applications in vibration control devices. Numerical models, calibrated with experimental laboratory tests from the literature, are used to investigate the dynamic response of three vibration control devices, built up of austenitic superelastic wires. The energy dissipation and re-centering capabilities, important features of these devices, are clearly illustrated by the numerical tests. Their sensitivity to ambient temperature and strain rate is also addressed. Finally, one of these devices is tested as a seismic passive vibration control system in a simplified numerical model of a railway viaduct, subjected to different ground accelerations.

Cismaşiu, C. The hybrid-{T}refftz Displacement Element for Static and Dynamic Structural Analysis Problems. Lisboa, Portugal: Instituto Superior Técnico, 2000. Abstract

The displacement model of the hybrid-{T}refftz finite element formulation is applied to the solution of geometrically and physically linear static and dynamic problems. As the approximation bases solve locally the governing system of differential equations, the errors in the approximation affect only the implementation of the boundary conditions. Potential and elastostatic problems are used to illustrate the enforcement of the boundary conditions and the convergence of the solutions in energy, stresses and displacements, under both p- and h-refinement sequences and their insensitivity to mesh distortion, incompressibility and positioning of the coordinate system of the approximation basis. Also illustrated is the use of elements with arbitrary geometry and the efficiency that can be reached by including in the bases the solutions associated with dominant local effects, in particular those associated with singular stress fields. An adaptive p-refinement algorithm that exploits the naturally hierarchical nature of the approximation bases is presented and assessed. The formulation is generalised for elastodynamic analysis in the frequency domain of both bounded and unbounded domains, which are modelled either with absorbing boundary conditions or with semi-infinite elements that satisfy the Sommerfeld condition. The performance of the formulation is illustrated with tests on the convergence of the solutions in energy, stresses and displacements and on their insensitivity to mesh distortion, wave length and position of the absorbing boundary, for a wide spectrum of forcing frequencies and under both p- and h-refinement sequences.

Cismaşiu, C., A. Narciso, and F. Amarante dos Santos. "Experimental Dynamic Characterization and Finite Element Updating of a Footbridge Structure." Journal of Performance of Constructed Facilities.10.1061/(ASCE)CF.1943-5509.0000615 (2014).Website
Cismaşiu, Corneliu, Filipe Amarante Dos P. Santos, Rui Da Silva A. Perdigão, Vasco M. S. Bernardo, Paulo X. Candeias, Alexandra R. Carvalho, and Luís M. C. Guerreiro. "Seismic Vulnerability Assessment of a RC Pedestrian Crossing." JOURNAL OF EARTHQUAKE ENGINEERING. X.X (2018): 1-19.
Cismaşiu, Corneliu, Pedro B. S. Silva, José V. Lemos, and Ildi Cismaşiu. "Seismic Vulnerability Assessment of a Stone Arch Using Discrete Elements." International Journal of Architectural Heritage (2021): 1-15. AbstractWebsite
Cismasiu, Corneliu, and Filipe Amarante Dos P. Santos. "Shape Memory Alloys." Ed. Book Corneliu edited by: Cismasiu. ISBN: 978-953-307-106-0. Croatia: Scyio, Publishing, 2010. 127-154. Abstract
Cismasiu, C., and Amarante F. P. dos Santos. "Towards a semi-active vibration control solution based on superelastic shape memory alloys." 15th WCEE. Lisbon, Portugal 2012. 2012_wcee_0379.pdf
Cismasiu, C., A. P. Ramos, I. D. Moldovan, D. F. Ferreira, and J. B. Filho. "Applied element method simulation of experimental failure modes in RC shear walls." Computers and Concrete. 19.4 (2017): 365-374.
Cismasiu, Corneliu, Filipe Amarante P. dos Santos, and Ana I. M. Rodrigues. "Experimental and FE updating techniques for the unseating vulnerability assessment of a footbridge structure." The 4th International Conference on Dynamics, Vibration and Control. Shanghai, China: Shanghai Institute of Applied Mathematics and Mechanics, 2014. icdvc_2014.pdf
by Cismasiu, Edited Corneliu Shape Memory Alloys. Scyio, 2010.Website
Cismasiu, Corneliu, and Filipe Pimentel Amarante dos Santos. "Shape Memory Alloys in Structural Vibration Control. Research at UNIC/DEC/FCT/UNL." International Conference "Tradition and Innovation". 60 Years of Civil Engineering Higher Education in Transilvania. Cluj-Napoca, Romania: UTCN, 2013. c60.pdf