@conference {16914, title = {Protection of infrastructures against explosions using ductile blast-energy absorption connectors}, booktitle = {17th International Conference on Structures under Shock and Impact - SUSI 2025}, year = {2025}, month = {9-11 June}, address = {Edinburgh, UK}, author = {Gabriel de Jesus Gomes and V{\'a}lter Jos{\'e} da Guia L{\'u}cio and Corneliu Cismasiu} } @article {16832, title = {Pressure coefficient distributions on Hyperbolic Paraboloid membranes by Numerical Fluid-Structure Interaction}, journal = {Latin American Journal of Solids and Structures}, volume = {25}, year = {2025}, author = {RM R{\'\i}os and Gamboa-Marrufo, M. and C. Cismasiu and JA Moreno-Herrera} } @article {MIHALI2025120534, title = {Impact of building model complexity on predicting external explosion consequences}, journal = {Engineering Structures}, volume = {339}, year = {2025}, note = {n/a}, pages = {120534}, abstract = {

Accurate blast models are essential for disaster management and emergency preparedness. Semi-empirical methods, which rely on free-field assumptions, struggle to provide precise data for complex building shapes because they ignore shock wave reflections. This research numerically investigates the effects of an explosion on a large building of complex geometrical configuration using blastFoam, estimating the fa{\c c}ade damage and assessing risks to occupants. To evaluate the importance of accurately modelling the building{\textquoteright}s geometry, four levels of detail were considered. Additionally, simulations were also performed using the Load Blast Enhanced (LBE) method from LS-DYNA to compare the estimates of this faster semi-empirical approach with those obtained through CFD analyses. The findings reveal that simpler CFD models are adequate for fa{\c c}ade analysis and injury assessment around the building but fall short for predicting injury distribution within interior spaces or between buildings. The LBE underestimates both structural damage and human injury levels, while detailed CFD highlights the importance of accounting for interior walls and windows to enhance blast pressure predictions.

}, keywords = {Blast propagation, CFD simulation, Complex geometrical configuration, Explosion effects}, issn = {0141-0296}, doi = {https://doi.org/10.1016/j.engstruct.2025.120534}, url = {https://www.sciencedirect.com/science/article/pii/S0141029625009253}, author = {A. Mihali and H. B. Rebelo and Cisma{\c s}iu, C. and N.H. Shaker} } @conference {16796, title = {Explosion consequences assessment in buildings with complex geometries}, booktitle = {19th International Symposium on Interaction of the Effects of Munitions with Structures}, year = {2024}, month = {9-13 Dec.}, address = {Bonn, Germany}, attachments = {https://docentes.fct.unl.pt/sites/default/files/cornel/files/mihali_isiems_2024_paper.pdf}, author = {Alin Mihali and Hugo B. Rebelo and Corneliu Cismasiu} } @article {doi:10.1177/20414196231183006, title = {Development of a high-performance blast energy-absorbing system for building structures}, journal = {International Journal of Protective Structures}, volume = {15}, year = {2024}, note = {

n/a

}, pages = {484-508}, abstract = {

Shock absorbers have been widely used in the automotive and aeronautical industries for many years. Inspired on these devices, the paper presents an analytical and numerical assessment of a high performance protective system for building structures against blast loads, which is composed of a shielding element connected to the main structure, at the floor levels, through ductile Energy Absorbing Connectors (EACs). The EACs exploit the external tube inversion mechanism to absorb a significant part of the imparted kinetic energy from the blast wave. While the system prototype has been developed in laboratory, it was characterized and tested in a full-scale blast testing campaign. A validated finite element model was used next to analyze its performance in a more demanding design scenario. The introduction of EACs notably reduces the peak horizontal loads and the kinetic energy transferred to the protected structure, being expected a significant reduction of the stresses in the supporting vertical elements, in addition to the protection of structural and non-structural members. These results encourage further studies of the presented protective system that can be potentially employed for a large variety of blast threat scenarios, especially when increasing the stand-off is not a possible/viable option and sensitive facilities have to be protected.

}, doi = {10.1177/20414196231183006}, url = {https://doi.org/10.1177/20414196231183006}, author = {Gabriel de Jesus Gomes and Valter Jos{\'e} da Guia L{\'u}cio and Corneliu Cismasiu} } @inbook {16290, title = {Experimental Research and Development on Blast Resistant Structures}, booktitle = {Advances on Testing and Experimentation in Civil Engineering, Springer Tracts in Civil Engineering}, year = {2023}, pages = {1-20}, publisher = {Springer Nature}, organization = {Springer Nature}, address = {Switzerland}, author = {Gomes, G. and Rebelo, H. and L{\'u}cio, V. and C. Cismasiu and Mingote, J.} } @article {16305, title = {Experimental Validation and Numerical Analysis of a High-Performance Blast Energy-Absorbing System for Building Structures}, journal = {Buildings}, volume = {13}, year = {2023}, pages = {1-20}, author = {Gabriel de Jesus Gomes and Valter Jos{\'e} da Guia L{\'u}cio and Corneliu Cismasiu and Jos{\'e} Luis Mingote} } @conference {16192, title = {Avalia{\c c}{\~a}o da vulnerabilidade s{\'\i}smica de um edif{\'\i}cio pombalino atrav{\'e}s de an{\'a}lise din{\^a}mica incremental}, booktitle = {Jornadas Portuguesas de Engenharia de Estruturas (JPEE)}, year = {2022}, month = {9-11 Nov.}, publisher = {LNEC, APEE, GPBE, SPES}, organization = {LNEC, APEE, GPBE, SPES}, address = {Lisboa}, attachments = {https://docentes.fct.unl.pt/sites/default/files/cornel/files/art_jpee2022_266_afccic_v8.pdf}, author = {Am{\^a}ndio Fonseca and Corneliu Cismasiu and Ildi Cismasiu} } @conference {16237, title = {Development of a high-performance blast energy-absorbing system for building structures}, booktitle = {AuxDefense2022 - 3rd World Conference on Advanced Materials for Defense}, year = {2022}, month = {6-8 Jul.}, address = {Guimar{\~a}es, Portugal}, author = {G. J. Gomes and L{\'u}cio, V J G and C. Cismasiu} } @conference {16240, title = {An{\'a}lise Comparativa entre Modelos Constitutivos para a Simula{\c c}{\~a}o de Elementos Estruturais de Bet{\~a}o Armado sujeitos a Cargas de Explos{\~a}o}, booktitle = {PROTEDES2022}, year = {2022}, month = {25 Nov.}, address = {Regi{\~a}o Sul da Ordem dos Engenheiros, Lisboa}, author = {Hugo Rebelo and Corneliu Cismasiu} } @conference {16241, title = {Comportamento de pain{\'e}is de vidro laminado {\`a} a{\c c}{\~a}o de explos{\~o}es - Gera{\c c}{\~a}o de curvas Press{\~a}o-Impulso}, booktitle = {PROTEDES2022}, year = {2022}, month = {25 Nov.}, address = {Regi{\~a}o Sul da Ordem dos Engenheiros, Lisboa}, author = {Tiago Oliveira and Pedro Matias and Corneliu Cismasiu} } @conference {16242, title = {Full Scale Blast testing of a High-Performance Energy-Absorbing System}, booktitle = {PROTEDES2022}, year = {2022}, month = {25 Nov.}, address = {Regi{\~a}o Sul da Ordem dos Engenheiros, Lisboa}, author = {G. J. Gomes and V{\'a}lter L{\'u}cio and Corneliu Cismasiu} } @conference {16239, title = {PROTEDES - Protection of Strategic Buildings Against Blast - Final Report}, booktitle = {PROTEDES2022}, year = {2022}, month = {25 Nov.}, address = {Regi{\~a}o Sul da Ordem dos Engenheiros, Lisboa}, author = {Stefan Marius Buru and V{\'a}lter L{\'u}cio and Corneliu Cismasiu} } @conference {15809, title = {AVALIA{\c C}{\~A}O DA VULNERABILIDADE S{\'I}SMICA DE UM PASSADI{\c C}O PEDONAL PARTINDO DA SUA IDENTIFICA{\c C}{\~A}O MODAL DIN{\^A}MICA}, booktitle = {TEST\&E 2022 3rd Conference on Testing and Experimentation in Civil Engineering Smart Technologies}, year = {2022}, month = {21-23 June}, address = {Campus da Caparica, Portugal}, attachments = {https://docentes.fct.unl.pt/sites/default/files/cornel/files/046.pdf}, author = {Pedro Silva and Jos{\'e} Nuno Varandas and Corneliu Cismasiu} } @conference {16238, title = {An{\'a}lise Experimental e Num{\'e}rica de Pain{\'e}is de Vidro Laminado Sujeitos {\`a} A{\c c}{\~a}o de Explos{\~o}es}, booktitle = {4.o ENCONTRO DE I\&D EM CI{\^E}NCIAS MILITARES {\textendash} ECM 2022}, year = {2022}, month = {16 Nov.}, publisher = {Academia da For{\c c}a A{\'e}rea}, organization = {Academia da For{\c c}a A{\'e}rea}, address = {Sintra}, author = {Tiago Oliveira and Pedro Matias and Corneliu Cismasiu} } @article {REBELO2021112279, title = {Robustness assessment of a deterministically designed sacrificial cladding for structural protection}, journal = {Engineering Structures}, volume = {240}, year = {2021}, note = {n/a}, pages = {112279}, abstract = {

Being able to efficiently mitigate the effects of blast loads on structures, sacrificial cladding solutions are increasingly used to protect structural elements from the effects of accidental explosions and/or terrorist attacks. The present study analyses the loss of effectiveness of a deterministically designed sacrificial cladding when variability in the material properties and uncertainties in the mechanical model are considered. The results of an experimental campaign are used to validate the numerical models that allow the deterministic design of a sacrificial cladding which successfully improves the blast resistant capabilities of a given structural element. Nonetheless, it is shown that, taking into account the probabilistic variability of key parameters is of vital importance when designing sacrificial cladding solutions, since, when not properly designed for the structural element it intends to protect, adding a sacrificial cladding might negatively impact its blast resistant capabilities. Additionally, it is concluded that the deterministic approach might be against safety. In the reported case study, when comparing the admissible charge weight yielding from the deterministic and probabilistic approaches, one verifies that the former allows a higher charge weight.

}, keywords = {Blast load, Probabilistic variability, Robustness assessment, Sacrificial cladding}, issn = {0141-0296}, doi = {https://doi.org/10.1016/j.engstruct.2021.112279}, url = {https://www.sciencedirect.com/science/article/pii/S0141029621004296}, author = {H. B. Rebelo and C. Cismasiu} } @article {doi:10.1080/15583058.2021.1963506, title = {Seismic Vulnerability Assessment of a Stone Arch Using Discrete Elements}, journal = {International Journal of Architectural Heritage}, year = {2021}, note = {n/a}, pages = {1-15}, publisher = {Taylor \& Francis}, abstract = {n/a}, doi = {10.1080/15583058.2021.1963506}, url = {https://www.tandfonline.com/doi/abs/10.1080/15583058.2021.1963506}, author = {Cisma{\c s}iu, Corneliu and Pedro B. S. Silva and Jos{\'e} V. Lemos and Ildi Cisma{\c s}iu} } @article {SANTOS2020113128, title = {Low velocity impact response of 3D printed structures formed by cellular metamaterials and stiffening plates: PLA vs. PETg}, journal = {Composite Structures}, year = {2020}, note = {n/a}, pages = {113128}, abstract = {

This work studies the low-velocity impact response of 3D-printed layered structures made of thermoplastic materials (PLA and PETg), which form sacrificial claddings for impact protection. The analyzed structures are composed of crushable cellular cores placed in between terminal stiffening plates. The cores tessellate either honeycomb hexagonal unit cells, or hexagonal cells with re-entrant corners, with the latter exhibiting auxetic response. The given results highlight that the examined PETg protectors exhibit higher energy dissipation ratios and lower restitution coefficients, as compared to PLA structures that have the same geometry. It is concluded that PETg qualifies as an useful material for the fabrication of effective impact protection gear through ordinary, low-cost 3D printers.

}, keywords = {Auxetic response, Cellular metamaterials, Low Velocity Impact, PETg, PLA}, issn = {0263-8223}, doi = {https://doi.org/10.1016/j.compstruct.2020.113128}, url = {http://www.sciencedirect.com/science/article/pii/S0263822320330543}, author = {F.A. Santos and Rebelo, H. and M. Coutinho and L.S. Sutherland and C. Cismasiu and I. Farina and F. Fraternali} } @conference {13156, title = {Avalia{\c c}{\~a}o da vulnerabilidade s{\'\i}smica de um arco em alvenaria utilizando o m{\'e}todo dos elementos discretos}, booktitle = {S{\'I}SMICA 2019 - 11{\textordmasculine} Congresso Nacional de Sismologia e Enhenharia S{\'\i}smica}, year = {2019}, month = {29 e 30 de Abril}, address = {Lisboa}, attachments = {https://docentes.fct.unl.pt/sites/default/files/cornel/files/final_sismica2019.pdf}, author = {Pedro Boto Semblano da Silva and Corneliu Cismasiu and Jos{\'e} Vieira de Lemos} } @conference {13491, title = {3D printed PLA sacrificial honeycomb cladding blast mitigation}, booktitle = {18th International Symposium for the Interaction of Munitions with Structures (ISIEMS)}, year = {2019}, month = {21-25 Oct.}, address = {Panama City Beach, FL, USA}, author = {H. B. Rebelo and D. Lecompte and Cisma{\c s}iu, C. and A. Jonet and B. Belkassem and A. Maazoun} } @article {13198, title = {Experimental and numerical investigation on 3D printed PLA sacrificial honeycomb cladding}, journal = {International Journal of Impact Engineering}, volume = {131}, year = {2019}, pages = {162-173}, url = {https://doi.org/10.1016/j.ijimpeng.2019.05.013}, author = {H. B. Rebelo and D. Lecompte and C. Cismasiu and A. Jonet and B. Belkassem and A. Maazoun} } @article {13105, title = {Exploratory study on geodesic domes under blast loads}, journal = { International Journal of Protective Structures}, year = {2019}, author = {Hugo Bento Rebelo and Amarante dos Santos, Filipe and Corneliu Cismasiu and Duarte Santos} } @conference {13493, title = {Blast Assessment {\textendash} A Methodology}, booktitle = {ISMS 2018 10th Anniversary Conference: Military Sciences and Future Security Challenges}, year = {2018}, month = {18-19 Oct.}, address = {War Studies University, Warsaw}, attachments = {https://docentes.fct.unl.pt/sites/default/files/cornel/files/gomes.pdf}, author = {Gomes, G. and L{\'u}cio, V. and C. Cismasiu and Rebelo, H.} } @conference {12716, title = {Experimental characterization of 3D-printed PLA under uniaxial high strain-rate loading}, booktitle = {AuxDefense 2018 {\textendash} 1st World Conference on Advanced Materials for Defense}, year = {2018}, month = {1-3 September}, address = {Lisbon}, attachments = {https://docentes.fct.unl.pt/sites/default/files/cornel/files/auxdefense_extabstract_v2.pdf}, author = {H. B. Rebelo and A. Greg{\'o}rio and P. A. R. Rosa and D. Lecompte and Cisma{\c s}iu, C.} } @article {12533, title = {Blast Assessment - uma metodologia de avalia{\c c}{\~a}o}, journal = {Constru{\c c}{\~a}o Magazine}, year = {2018}, pages = {18 - 23}, author = {Gomes G and L{\'u}cio V and Cismasiu C and Rebelo H B} } @article {12715, title = {Cyclic Instability of Shape-Memory Alloys in Seismic Isolation Systems}, journal = {International Journal of Structural Glass and Advanced Materials Research}, year = {2018}, pages = {1-14}, author = {Amarante dos Santos, Filipe and Corneliu Cismasiu and Francisco Braz Fernandes} } @article {12776, title = {Dynamic Characterisation and Finite Element Updating of a RC Stadium Grandstand}, journal = {Buildings}, volume = {8}, year = {2018}, pages = {141, 1-19}, author = {Filipe Santos and Corneliu Cismasiu and Ildi Cismasiu and Chiara Bedon} } @article {12534, title = {Modela{\c c}{\~a}o tridimensional de ondas de choque em LS-DYNA}, journal = {Constru{\c c}{\~a}o Magazine}, year = {2018}, pages = {24 - 28}, author = {C. Cismasiu and J. R. G. Ferreira and H. B. Rebelo} } @article {12301, title = {Seismic Vulnerability Assessment of a RC Pedestrian Crossing}, journal = {JOURNAL OF EARTHQUAKE ENGINEERING}, volume = {X}, year = {2018}, pages = {1-19}, author = {Cisma{\c s}iu, Corneliu and Filipe P. Amarante Dos Santos and Rui A. Da Silva Perdig{\~a}o and Vasco M. S. Bernardo and Paulo X. Candeias and Alexandra R. Carvalho and Lu{\'\i}s M. C. Guerreiro} } @conference {11153, title = {A Comparison between Three Air Blast Simulation Techniques in LS-DYNA}, booktitle = {11th European LS-DYNA Conference 2017}, year = {2017}, month = {9-11 May}, publisher = {DYNAMORE}, organization = {DYNAMORE}, address = {Salzburg, Austria}, author = {Hugo Bento Rebelo and Corneliu Cismasiu} } @conference {11672, title = {Estimation of the tensile force in the stay-cables of Salgueiro Maia Bridge using ambient vibration tests}, booktitle = {ISDAC2017 - International Symposium on the Dynamics and Aerodynamics of Cables}, year = {2017}, month = {30-37 Oct.}, publisher = {FEUP}, organization = {FEUP}, address = {Porto}, attachments = {https://docentes.fct.unl.pt/sites/default/files/cornel/files/artigo_isdac_v5_ec.pdf}, author = {Ana Joaquim and Corneliu Cismasiu and Filipe Santos and Elsa Caetano} } @conference {11696, title = {Seismic retrofitting of an existing steel structure}, booktitle = {17th International Multidisciplinary Scientific GeoConference SGEM 2017}, year = {2017}, month = {29 June - 5 July}, address = {Albena; Bulgaria}, url = {https://www.scopus.com/sourceid/21100274701?origin=recordpage}, author = {Campian, C. and Pop, M. and C. Cismasiu and Josza, T. and Popa, A.} } @conference {11154, title = {Numerical Simulation of Blast Effects on Fibre Grout Strengthened RC Panels}, booktitle = {International Conference on Structural and Mechanical Engineering for Security and Prevention 2017}, year = {2017}, month = {14-16 June}, address = {Prague, Czech Republic}, author = {Hugo Miguel Bento Rebelo and Corneliu Cismasiu and V{\'a}lter Jos{\'e} da Guia L{\'u}cio and Manuel Tom{\'a}s Marques do Souto Gon{\c c}alves and Gabriel de Jesus Gomes and Jos{\'e} Pedro Fernandes Basto} } @conference {cismasiu2017, title = {Numerical Simulation of Blast Effects on Fibre Grout Strengthened RC Panels}, booktitle = {Structural and Mechanical Engineering for Security and Prevention}, series = {Key Engineering Materials}, volume = {755}, year = {2017}, note = {n/a}, month = {10}, pages = {18{\textendash}30}, publisher = {Trans Tech Publications}, organization = {Trans Tech Publications}, abstract = {

The present paper aims to examine the potential of the Applied Element Method (AEM) in simulating the blast effects in RC panels. The numerical estimates are compared with the results obtained in an experimental campaign designed to investigate the effectiveness of fibre grout for strengthening full scale RC panels by comparing the effects that a similar blast load produces in a reference and the strengthened panel. First, a numerical model of the reference specimen was created in the software Extreme Loading for Structures and calibrated to match the experimental results. With no further calibration, the fibre reinforced grout strengthening was added and the resulting numerical model subjected to the same blast load. The experimental blast effects on both reference and strengthened panels, despite the lack of high speed measurement equipment (pressure, strains and displacements sensors), compare well with the numerical estimates in terms of residual and maximum displacements, showing that, once calibrated, the AEM numerical models can be successfully used to simulate blast effects in RC panels.

}, keywords = {applied element method, Blast Effect, Fibre Reinforced Grout, Non-Linear Dynamic Analysis}, doi = {10.4028/www.scientific.net/KEM.755.18}, author = {Hugo Bento Rebelo and Cisma{\c s}iu, Corneliu and L{\'u}cio, V{\'a}lter J.G. and Gon{\c c}alves, Manuel T.M.S. and Gomes, Gabriel J. and Basto, Jos{\'e} P.F.} } @article {11023, title = {Applied element method simulation of experimental failure modes in RC shear walls}, journal = {Computers and Concrete}, volume = {19}, year = {2017}, pages = {365-374}, attachments = {https://docentes.fct.unl.pt/sites/default/files/cornel/files/2017_applied_element_method_simulation_of_experimental_failure_modes_in_rc_shear_walls.pdf}, author = {C. Cismasiu and Ramos, A. P. and Moldovan, I. D. and Ferreira, D. F. and Filho, J. B.} } @conference {9349, title = {Simula{\c c}{\~a}o Num{\'e}rica do Efeito de Explosivos em Pain{\'e}is de Bet{\~a}o Armado Refor{\c c}ados com Argamassas Armadas}, booktitle = {BE2016}, year = {2016}, month = {2-4 Nov.}, address = {FCTUC}, author = {Hugo Rebelo and Gabriel Gomes and Corneliu Cismasiu} } @proceedings {8373, title = {COMPORTAMENTO S{\'I}SMICO DE LIGA{\c C}{\~O}ES EM PASSADI{\c C}OS PR{\'E}-FABRICADOS}, journal = {10{\textordmasculine} Congresso Nacional de Sismologia e Engenharia S{\'\i}smica}, year = {2016}, pages = {1-12}, address = {Ponta Delgada}, attachments = {https://docentes.fct.unl.pt/sites/default/files/cornel/files/artigosismica2016_submetido.docx}, author = {F. Santos and C. Cismasiu and R. Perdig{\~a}o and V. Bernardo and J. Sampayo and P. Candeias and Costa, A. and Carvalho, A. and L. Guerreiro} } @article {8032, title = {Smart glazed cable facade subjected to a blast loading}, journal = {Proceedings of the Institution of Civil Engineers - Structures and Buildings}, volume = {3}, year = {2016}, pages = {223-232}, author = {Amarante dos Santos, Filipe and Corneliu Cismasiu and Chiara Bedon} } @article {dos Santos13092016, title = {Adaptive underslung beam using shape-memory alloys for frequency-tuning}, journal = {Journal of Intelligent Material Systems and Structures}, year = {2016}, note = {n/a}, abstract = {

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.

}, doi = {10.1177/1045389X16667558}, url = {http://jim.sagepub.com/content/early/2016/09/12/1045389X16667558.abstract}, author = {Amarante dos Santos, Filipe and Cisma{\c s}iu, Corneliu} } @conference {7324, title = {Passive and active control systems for adaptive glazing systems and envelopes}, booktitle = {European COST Action TU1403 "Adaptive facades network" Industry Workshop}, year = {2015}, month = {September 2015}, address = {Delft, The Netherlands}, attachments = {https://docentes.fct.unl.pt/sites/default/files/cornel/files/tu1403_poster_template_2015_04_30_final_02_cb.pdf}, author = {Chiara Bedon and Filipe Santos and Claudio Amadio and Corneliu Cismasiu} } @article {dos2015smart, title = {Smart glazed cable fa{\c c}ade subjected to a blast loading}, journal = {Proceedings of the Institution of Civil Engineers-Structures and Buildings}, year = {2015}, note = {

n/a

}, pages = {1{\textendash}10}, publisher = {Thomas Telford Ltd}, abstract = {

This paper investigates the dynamic behaviour of cable-supported glazing fa{\c c}ades
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
fa{\c c}ade components. As shown, both the glass panels and the cable system are able to
properly accommodate the incoming impulsive loads, typically involving extreme ...

}, author = {Amarante dos Santos, Filipe and Corneliu Cismasiu and Chiara Bedon} } @conference {6055, title = {Experimental and FE updating techniques for the unseating vulnerability assessment of a footbridge structure}, booktitle = {The 4th International Conference on Dynamics, Vibration and Control}, year = {2014}, month = {August 23-25, 20}, publisher = {Shanghai Institute of Applied Mathematics and Mechanics}, organization = {Shanghai Institute of Applied Mathematics and Mechanics}, address = {Shanghai, China}, attachments = {https://docentes.fct.unl.pt/sites/default/files/cornel/files/icdvc_2014.pdf}, author = {Corneliu Cismasiu and Filipe P. Amarante dos Santos and Ana I.M. Rodrigues} } @article {5780, title = {Experimental Dynamic Characterization and Finite Element Updating of a Footbridge Structure}, journal = {Journal of Performance of Constructed Facilities}, year = {2014}, url = {http://dx.doi.org/10.1061/(ASCE)CF.1943-5509.0000615}, author = {Cisma{\c s}iu, C. and Narciso, A. and Amarante dos Santos, F} } @article {6056, title = {Smart glass facade subjected to wind loadings}, journal = {Structures and Buildings}, volume = {167}, year = {2014}, pages = {1-10}, attachments = {https://docentes.fct.unl.pt/sites/default/files/cornel/files/stbu1300011_offprint.pdf}, author = {Filipe P. Amarante dos Santos and Corneliu Cismasiu and Pedro F. Gon{\c c}alves and Gamboa-Marrufo, Mauricio} } @proceedings {6777, title = {Vulnerabilidade e refor{\c c}o s{\'\i}smico de uma passagem superior pedonal pr{\'e}-fabricada}, journal = {5as Jornadas Portuguesas de Engenharia de Estruturas}, year = {2014}, address = {Lisboa}, attachments = {https://docentes.fct.unl.pt/sites/default/files/cornel/files/artigo_jpee2014.pdf}, author = {Vasco Bernardo and Andr{\'e} Oliveira and Amarante dos Santos, Filipe and Corneliu Cismasiu} } @conference {5055, title = {Shape Memory Alloys in Structural Vibration Control. Research at UNIC/DEC/FCT/UNL}, booktitle = {International Conference "Tradition and Innovation". 60 Years of Civil Engineering Higher Education in Transilvania}, year = {2013}, month = {7-9 Nov.}, publisher = {UTCN}, organization = {UTCN}, address = {Cluj-Napoca, Romania}, attachments = {https://docentes.fct.unl.pt/sites/default/files/cornel/files/c60.pdf}, author = {Corneliu Cismasiu and Filipe Pimentel Amarante dos Santos} } @inbook {5270, title = {Bridge Hinge-Restrainers Built up of NITI Superelastic Shape-Memory Alloys}, booktitle = {New Trends in Smart Technologies }, year = {2013}, pages = {195-203}, publisher = {Fraunhofer Verlag}, organization = {Fraunhofer Verlag}, address = {Saarbr{\"u}cken}, author = {F. P. Amarante dos Santos and C. Cismasiu}, editor = {Christian Boller and Hartmut Janocha} } @conference {2751, title = {Towards a semi-active vibration control solution based on superelastic shape memory alloys}, booktitle = {15th WCEE}, year = {2012}, month = {24-28 September}, address = {Lisbon, Portugal}, attachments = {https://docentes.fct.unl.pt/sites/default/files/cornel/files/2012_wcee_0379.pdf}, author = {C. Cismasiu and F. P. Amarante dos Santos} } @conference {Tue_Jul_12_11:46:50_WEST_201, title = {Bridge hinge-restrainers built up of NiTi superelastic shape-memory alloys}, booktitle = {Smart Structures and Materials (SMART{\textquoteright}11)}, series = {5th ECCOMAS Thematic Conference on Smart Structures and Materials SMART{\textquoteright}11}, year = {2011}, note = {

n/a

}, month = {July 6-8}, address = {Saarbr{\"u}cken, Germany}, abstract = {

n/a

}, attachments = {https://docentes.fct.unl.pt/sites/default/files/cornel/files/santos_2011.pdf}, author = {F. P. Amarante dos Santos and C. Cismasiu} } @article {Wed_Jun_29_09:23:19_WEST_201, title = {Hybrid-Trefftz displacement element for poroelastic media}, journal = {Computational Mechanics}, year = {2011}, note = {n/a}, pages = {1-15}, abstract = {

The elastodynamic response of saturated poroelastic media is modelled approximating independently the solid and seepage displacements in the domain and the force and pressure components on the boundary of the element. The domain and boundary approximation bases are used to enforce on average the dynamic equilibrium and the displacement continuity conditions, respectively. The resulting solving system is Hermitian, except for the damping term, and its coefficients are defined by boundary integral expressions as a Trefftz basis is used to set up the domain approximation. This basis is taken from the solution set of the governing differential equation and models the free-field elastodynamic response of the medium. This option justifies the relatively high levels of performance that are illustrated with the time domain analysis of unbounded domains.

}, keywords = {Hybrid-Trefftz elements }, url = {http://dx.doi.org/10.1007/s00466-011-0612-7}, author = {de Freitas, J. and Moldovan, I. and Cisma{\c s}iu, C.} } @book {Thu_Nov__4_15:45:16_WET_2010, title = {Shape Memory Alloys}, year = {2010}, note = {n/a}, month = {October}, publisher = {Scyio}, organization = {Scyio}, url = {http://www.dec.fct.unl.pt/seccoes/S_Estruturas/docentes/cornel/papers/SCIYO_Shape_Memory_Alloys.pdf}, author = {Edited by Corneliu Cismasiu} } @inbook {Thu_Oct_14_08:27:03_WEST_201, title = {Shape Memory Alloys}, series = {ISBN: 978-953-307-106-0}, year = {2010}, note = {n/a}, month = {August}, pages = {127-154}, publisher = {Scyio, Publishing}, organization = {Scyio, Publishing}, chapter = {Numerical simulation of a semi-active vibration control device based on superelastic shape memory alloy wires}, address = {Croatia}, abstract = {n/a}, author = {Corneliu Cismasiu and Filipe P. Amarante Dos Santos}, editor = {Book edited by: Corneliu Cismasiu} } @article {Wed_Jul__8_11:09:18_WEST_200, title = {Comparison Between Two SMA Constitutive Models for Seismic Applications}, journal = {Journal of Vibration and Control}, volume = {16}, number = {6}, year = {2010}, note = {

n/a

}, month = {April}, pages = {897-914}, abstract = {

This paper analyses and compares the dynamic behavior of superelastic shape memory alloy (SMA) systems based on two different constitutive models. The first model, although being able to describe the response of the material to complex uniaxial loading histories, is temperature and rate independent. Thesecond model couples the mechanical and kinetic laws of the material with a balance equation considering the thermal effects. After numerical validation and calibration, the behavior of these two models is tested in single degree of freedom dynamic systems, with SMAs acting as restoring elements. Different dynamic loads are considered, including artificially generated seismic actions, in a numerical model of a railway viaduct. Finally, it is shown that, in spite of its simplicity, the temperature- and rate-independent modelproduces a set of very satisfying results. This, together with its robustness and straightforward computational implementation, yields a very appealing numerical tool to simulate superelastic passive control applications.

}, keywords = {constitutive models, passive vibration control, seismic applications, Shape memory alloys}, url = {http://jvc.sagepub.com/content/16/6/by/author}, author = {F. P. Amarante dos Santos and C. Cismasiu} } @conference {Tue_May_20_13:39:57_WEST_200, title = {Comparison Between Two {SMA} Constitutive Models for Seismic Applications}, booktitle = {Twelfth Conference on Nonlinear Vibrations, Dynamics, and Multibody Systems}, year = {2008}, note = {n/a}, month = {June 1-5}, address = {Blacksburg, VA 24061}, abstract = {n/a}, keywords = {constitutive models, passive vibration control, seismic applications, SMAs}, author = {F. P. Amarante dos Santos and C. Cismasiu} } @article {Fri_Mar_14_10:37:52_WET_2008, title = {Numerical simulation of superelastic shape memory alloys subjected to dynamic loads}, journal = {Smart Materials and Structures}, volume = {17}, number = {2}, year = {2008}, note = {

n/a

}, month = {April}, pages = {025036 (12pp)}, abstract = {

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.

}, url = {http://iopscience.iop.org/0964-1726/17/2/025036/}, author = {Corneliu Cismasiu and Filipe P. Amarante dos Santos} } @conference {Fri_Oct_19_10:14:25_WEST_200, title = {Shape memory alloys in structural vibration control}, booktitle = {EVACES{\textquoteright}07 - Experimental Vibration Analysis for Civil Engineering Structures}, year = {2007}, note = {n/a}, month = {24-26 October}, address = {FEUP, Porto, Portugal}, abstract = {

The unique superelastic behaviour exhibited by 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 the SMAs particularly suitable for applications in vibration control devices. Numerical models, calibrated with experimental laboratory tests, are used to investigate the dynamic response of vibration control devices. These devices are built up of austenitic superelastic wires. The energy dissipation and re-centring capabilities, important features of these devices, are clearly illustrated by the numerical tests. One of these devices is tested as a seismic passive vibration control system in a simplified numerical model of a railway viaduct.

}, keywords = {SMA, vibration control}, url = {http://www.dec.fct.unl.pt/FuncionalidadesRestritas/Conferencias/EVACES_07/papers/cd_paper_pag_641.pdf}, author = {Santos, F. P. and C. Cismasiu} } @article {Thu_Mar_11_16:46:02_WET_2004, title = {Numerical simulation of ballistic impact on composite laminates}, journal = {International Journal of Impact Engineering}, volume = {31}, number = {3}, year = {2005}, note = {

n/a

}, month = {March}, pages = {289-306}, abstract = {

The paper reports experimental and numerical simulation of ballistic impact problems on thin composite laminated plates reinforced with Kevlar 29. Ballistic impact was imparted with simulated fragments designed in accordance with STANAG-2920 on plates of different thickness. Numerical modelling was developed and used to obtain an estimate for the limit perforation velocity V50 and simulate failure modes and damage. Computations were carried out using a commercial code based on nite differences and values obtained are compared with the experimental data to evaluate the performance of the simulation. Good correlation between computational simulation and experimental results was achieved, both in terms of deformation and damage of the laminates. Future work is advanced to include the interposition of an outer ceramic layer as well as examining the influence of dry-wet and temperature cycles on the mechanical strength of the plates and their temporal evolution under accelerated ageing.

}, keywords = {Ballistic impact, Composite Materials, Non-Linear Transient Dynamics}, author = {Silva, M. A. G. and Cisma{\c s}iu, C. and Chiorean, C. G.} } @booklet {Fri_Feb_23_16:42:55_WET_2007, title = {Din{\^a}mica de s{\'o}lidos - fichas da disciplina. DEC/FCT}, year = {2004}, note = {

n/a

}, abstract = {

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}, url = {http://www.dec.fct.unl.pt/seccoes/S_Estruturas/Dinamica_Solidos/resumos.html}, author = {Cisma{\c s}iu, C.} } @conference {Tue_Dec__2_16:32:22_WET_2003, title = {Low velocity impact on laminates reinforced with {P}olyethylene and {A}ramidic fibres}, booktitle = {Computational Methods in Engineering and Science. Proceedings of the 9th International Conference EPMESC IX}, year = {2003}, note = {n/a}, month = {25-28 November}, pages = {843-849}, publisher = {A.A.Balkema Publishers}, organization = {A.A.Balkema Publishers}, address = {Macao, China}, abstract = {

The present study reports low velocity impact tests on composite laminate plates reinforced either with Kevlar 29 or Dyneema. The tests are produced using a Rosand Precision Impact tester. The experimental results obtained for Kevlar 29 are simulated numerically. The deflection history and the peak of the impact force are compared with experimental data and used to calibrate the numerical model.

}, keywords = {Composite Materials, Low Velocity Impact, Non-Linear Transient Dynamics}, url = {http://www.dec.fct.unl.pt/seccoes/S_Estruturas/docentes/cornel/papers/epmescIX.pdf}, author = {Silva, M. A. G. and Cisma{\c s}iu, C. and Chiorean, C. G.}, editor = {Iu, V.P. and Lamas, L.N. and Li, Y.-P. and Mok, K.M.} } @conference {Tue_Nov_18_10:02:55_WET_2003, title = {Ballistic Simulation of Impact on Composite Laminates}, booktitle = {Proceedings of the International Conference Constructions 2003}, volume = {2}, year = {2003}, note = {n/a}, month = {16-17 May}, pages = {139-146}, publisher = {The Technical University of Cluj-Napoca}, organization = {The Technical University of Cluj-Napoca}, address = {Cluj-Napoca, Romania}, abstract = {

The paper reports on numerical simulation of impact problems on fiber reinforced plastic composite laminated plates reinforced with Kevlar 29. The ballistic impact caused by STANAG-2920 projectile is analyzed to obtain an estimate for the V50 and the global damage. All estimate have been carried out using the finite difference numerical code AUTODYN-3D, are compared with the experimental data to illustrate the performance of the simulation. Good correlation between resulting simulations and experimental results is demonstrated both in terms of deformation and damage of the laminates and ballistic performance.

}, keywords = {Ballistic impact, Composite Materials, Non-Linear Transient Dynamics}, url = {http://www.dec.fct.unl.pt/seccoes/S_Estruturas/docentes/cornel/papers/Impact_Rom.pdf}, author = {Silva, M. A. G. and Cisma{\c s}iu, C. and Chiorean, C. G.} } @article {Tue_Nov_18_09:51:12_WET_2003, title = {Adaptive p-refinement of hybrid-{T}refftz finite element solutions}, journal = {Finite Elements in Analysis and Design}, volume = {39}, year = {2003}, note = {

n/a

}, pages = {1095-1121}, abstract = {

An adaptive p-refinement procedure for the implementation of the displacement model of the hybrid-{T}refftz finite element formulation is presented. The procedure is designed to select and implement automatically the degrees of freedom in the domain (displacements) and on the boundary (surface forces) of the element to attain a prescribed level of accuracy. This accuracy is measured on the strain energy of the system for a prescribed finite element mesh. Local measures of error can be easily accounted for. The performance of the adaptive procedure suggested is illustrated using two-dimensional potential problems.

}, keywords = {hybrid finite elements, p-adaptivity, Trefftz method}, author = {Freitas, J. A. T. and Cisma{\c s}iu, C.} } @article {Tue_Nov_18_10:06:17_WET_2003, title = {Hybrid-{T}refftz displacement element for spectral analysis of bounded and unbounded media}, journal = {International Journal of Solids and Structures}, volume = {40}, year = {2003}, note = {

n/a

}, pages = {671-699}, abstract = {

The hybrid-{T}refftz displacement element is applied to the elastodynamic analysis of bounded and unbounded media in the frequency domain. The displacements are approximated in the domain of the element using local solutions of the wave equation, the Neumann conditions are enforced directly and the surface forces are approximated on the Dirichlet and inter-element boundaries of the finite element mesh. Two alternative elements are developed to model unbounded media, namely a finite element with absorbing boundaries and an unbounded element that satisfies explicitly the Sommerfeld condition. The finite element equations are derived from the fundamental relations of elastodynamics written in the frequency domain. The numerical implementation of these equations is discussed and numerical tests are presented to assess the performance of the formulation.

}, keywords = {hybrid-{T}refftz displacement elements, spectral analysis, unbounded media}, author = {Freitas, J. A. T. and Cisma{\c s}iu, C.} } @booklet {Fri_Feb_23_16:48:55_WET_2007, title = {Teoria de Estruturas {I} - fichas da disciplina. {DEC/FCT}}, year = {2003}, note = {n/a}, abstract = {n/a}, author = {Cisma{\c s}iu, C.} } @booklet {Fri_Feb_23_16:46:18_WET_2007, title = {Modela{\c c}{\~a}o computacional em engenharia civil - aulas pr{\'a}ticas. DEC/FCT}, year = {2002}, note = {

n/a

}, abstract = {

n/a

}, url = {http://www.dec.fct.unl.pt/seccoes/S_Estruturas/Modelacao_Fisica_e_Matematica_em_Engenharia/AulasPraticasHTML/AulasPraticas.html}, author = {Cisma{\c s}iu, C. and Silva, M. A. G.} } @article {Fri_Dec__5_09:15:45_WET_2003, title = {Developments with hybrid-{T}refftz stress and displacement elements}, journal = {Computer Assisted Mechanics and Engineering Sciences}, volume = {8}, year = {2001}, note = {

n/a

}, pages = {289-311}, abstract = {

The paper reports on the work on hybrid-{T}refftz finite elements developed by the Structural Analysis Research Group, ICIST, Technical University of Lisbon. A dynamic elastoplastic problem is used to describe the technique used to establish the alternative stress and displacement models of the hybrid-{T}refftz finite element formulations. They are derived using independent time, space and finite element bases, so that the resulting solving systems are symmetric, sparse, naturally $p$-adaptive and particularly well suited to parallel processing. The performance of the hybrid-{T}refftz stress and displacement models is illustrated with a number of representative static and dynamic applications of elastic and elastoplastic structural problems.

}, keywords = {dynamics, elasticity, elastoplasticity, Hybrid-{T}refftz elements}, author = {Freitas, J. A. T. and Cisma{\c s}iu, C.} } @booklet {Fri_Feb_23_16:50:55_WET_2007, title = {Resist{\^e}ncia dos materiais - Licenciatura em Engenharia Geol{\'o}gica. DEC/FCT}, year = {2001}, note = {

n/a

}, abstract = {

n/a

}, author = {Cisma{\c s}iu, C. and Cisma{\c s}iu, I.} } @mastersthesis {Tue_Nov_18_09:41:30_WET_2003, title = {The hybrid-{T}refftz Displacement Element for Static and Dynamic Structural Analysis Problems}, year = {2000}, note = {n/a}, month = {September}, school = {Instituto Superior T{\'e}cnico}, type = {phd}, address = {Lisboa, Portugal}, 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.

}, keywords = {Adaptive methods, Elastostatics, Finite elements, Hybrid-{T}refftz displacement model, Spectral elastodynamics, Unbounded domains}, url = {Http://www.dec.fct.unl.pt/seccoes/S_Estruturas/docentes/cornel/papers/Thesis.pdf}, author = {Cisma{\c s}iu, C.} } @article {1134, title = {Comparative analysis of hybrid-Trefftz stress and displacement elements}, journal = {Archives of Computational Methods in Engineering. State of the art reviews}, volume = {6}, year = {1999}, pages = {35-39}, author = {Freitas, J. A. T. and C. Cismasiu and Z. M. Wang} } @article {Fri_Dec__5_09:32:04_WET_2003, title = {Numerical implementation of hybrid-{T}refftz displacement elements}, journal = {Computers \& Structures}, volume = {73}, year = {1999}, note = {

n/a

}, pages = {207-225}, abstract = {

The numerical implementation of the displacement model of the hybrid-{T}refftz finite element formulation is presented. The geometry of the supporting element is not constrained a priori. Unbounded, non-convex and multiply connected elements can be used. The approximation basis is naturally hierarchical and very rich. It is constructed on polynomial solutions of the governing differential equation, and extended to include the particular terms known to model accurately important local effects, namely the singular stress patterns due to cracks or point loads. Numerical and semi-analytical methods are used to compute the finite element matrices and vectors, all of which present boundary integral expressions. Appropriate procedures to store, manipulate and solve symmetric highly sparse systems are used. The characteristics of the finite element solving system in terms of sparsity and conditioning are analysed, as well as its sensitivity to the effects of mesh distortion, incompressibility and rotation of the local reference systems. Benchmark tests are used also to illustrate the performance of the element in the estimation of displacements, stresses and stress intensity factors.

}, keywords = {finite element displacement model, hybrid-{T}refftz}, author = {Freitas, J. A. T. and Cisma{\c s}iu, C.} }