Filipe Amarante dos Santos

Verified

Filipe verified their affiliation via an institutional email.

Learn more

Verified

Filipe verified their affiliation via an institutional email.

Learn more

• PhD MSc
• Professor (Associate) at Universidade NOVA de Lisboa

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-...

Superelastic tensegrity systems are prestressed structures composed by bars and cables in which some cables are realized with superelastic shape-memory alloys. These systems combine the peculiar features of tensegrity structures with those of shape-memory alloys and are particularly suitable for adaptive and variable-geometry systems. The main goal...

The present paper explores the capabilities of a tensegrity-inspired tower with regard to frequency tuning by shape morphing. To change the configuration of the proposed structure, shape-memory-alloy (SMA) actuators are used. This actuation principle also takes advantage of the variation of the elastic modulus of SMAs associated with the martensiti...

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 transforma...

The paper addresses the seismic vulnerability assessment of a multi-span footbridge, prone to span unseating due to shorter seat lengths. The structure is representative of a series of pedestrian crossings located in the Southern part of Portugal, a region with a relevant seismicity. A probabilistic approach allows considering the variability of th...

The mechanical analysis of photovoltaics and building integrated photovoltaics is a key step for their optimal design and certification, and requires careful consideration, alongside solar power, durability and functionality issues. The solar cells are encapsulated in thin interlayers that are usually composed of a viscoelastic Ethylene–Vinyl Aceta...

In Part I of this study, it was shown that all the three known types of monohedral hexagonal tessellations of the plane, those composed of equal irregular hexagons, have just a single deformation mode when tiles are considered as rigid bodies hinged to each other along the edges. A gallery of tessellated plates was simulated numerically to demonstr...

The control of the shape of complex metasurfaces is a challenging task often addressed in the literature. This work presents a class of tessellated plates able to deform into surfaces of preprogrammed shape upon activation by any flexural load and that can be controlled by a single actuator. Quadric metasurfaces are obtained from infinitesimal orig...

We investigate a design concept for thin tiled plates having exactly one degree of freedom. A tiled plate is realized as a tessellation composed by rigid tiles hinged to each other along the sides. The plate can deform in just one way, that is, into a predetermined surface. The family of tilings we consider, the monohedral hexagonal one, with eithe...

Tensegrity metamaterials are a type of artificial materials that can exploit the tunable nonlinear mechanical behavior of the constituent tensegrity units. Here, we present reduced-order analytical models describing the prestrain-induced bistable effect of two particular tensegrity units. Closed-form expressions of the critical prestrain at which a...

Weathering and operational conditions, as known, have significant impact on typical constituent materials which are used for many construction applications. Among others, structural glass solutions can suffer for these effects in terms of major modification of material properties of interlayers, bonds, connections, gaskets and polymeric components...

This paper is focused on the study of innovative bi-stable supports to improve the impact performance of point-fixed glass panels, for typical use in facades. To mitigate the effects of impact and reduce potential risk for people, the introduction of innovative, bi-stable, mitigation devices between the fixing system and the primary building struct...

The interest in novel energy dissipation devices that offer advanced functionalities for optimal performance in state-of-the-art engineering applications is growing. In this regard, a highly tunable and innovative dissipator has been developed. This dissipator features movement amplification capabilities resulting from the radial replication of a u...

For structural design purposes, human-induced loads on pedestrian systems can be described by several simplified (i.e., deterministic equivalent-force models) or more complex computational approaches. Among others, the Spring-Mass-Damper (SMD), Single Degree of Freedom (SDOF) model has been elaborated by several researchers to describe single pedes...

This paper is an exploratory study on the dynamic response of a building model equipped with multiple curved-surface sliders. By using, as benchmarks, numerical models of non-isolated and conventional base-isolated systems, it is possible to show the optimized acceleration response of a building with distributed isolation, for a wider frequency inp...

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...

Tensegrity structures have recently shown great potential as bracing devices for seismic control due to their unique ability to passively dissipate energy in structures subjected to severe deformations. Indeed, behaving as nonlinear springs, they are able to dissipate a great amount of energy energy during mechanical loading-unloading cycles. Plana...

The design of buildings with a limited environmental impact and improved energy efficiency is nowadays of fundamental importance to face the challenge of reducing pollution and saving natural resources, without giving up comfort, indoor air quality and well-being. In fact, it is well known that the building industry is one of the largest consumers...

Nonlinear metamaterials are progressively emerging as structured materials that can tune their responses to the level of the applied stress/strain or the amplitude of traveling waves. The class of nonlinear metamaterials with tensegrity architecture are particularly interesting: their mechanical behavior can be effectively adjusted by acting on int...

Developing suitable connection systems for Glass Fiber Reinforced Polymer (GFRP) members started at least three decades ago [1] and is continuing today [2]. Based on previous experimental results by Smith et al. [3,4], GFRP profiles with closed cross-sections (i.e., tubular sections) provide certain mechanical properties that are superior to those...

To optimize the seismic performance prescribed by modern structural codes, buildings and infrastructures must provide adequate safety for design level earthquake excitations, with limited levels of damage. This paper deals with the computational modelling of a bracing system with tensegrity architecture, which operates as a lightweight mechanical a...

A continuum elastic plate has infinite degrees of freedom: according to the applied loads, it assumes the shape that the minimization of the total energy prescribes, in dependence of the material it is made of. The possibility to control the shape of a morphing structure is receiving an increasing attention in several fields; in this connection, if...

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 uni...

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 uni...

This paper presents with an effective and fast approach to the optimization of the pretension forces in arched bridges with suspended deck, which makes use of the influence matrix method (IMM). The given cable-tensioning procedure leads to a linear system of equations with a reduced number of unknowns and can be effectively implemented within activ...

This work is focused on the computational design of tensegrity shading systems of energy efficient buildings which mitigate air conditioning consumption and optimize the energy performance of the building. It is concerned with the design of active solar façade screens based on lightweight tensegrity units, which are easily integrated with energy ha...

Recent studies have investigated the use of origami sunscreens with tensegrity architecture for the design of active solar façades of energy efficient buildings. This paper presents a mechanical study on the dynamic response of shading screens that are formed by origami panels activated trough the tensioning and relaxation of selected strings. The...

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...

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...

This paper presents a novel application of tensegrity systems as lightweight and noninvasive braces for seismically resistant structures. The analyzed braces consist of D-bar systems equipped with shape memory alloy cables with superelastic response. These structures are able to markedly amplify the applied longitudinal displacements in the transve...

This paper explores the capabilities of a superelastic, tensegrity-inspired bracing system acting as a seismic protection device. The metamaterial-type response of the proposed structure, which is related to its geometry more than to the nature of the employed materials, yields a passive control device with optimized structural response. It operate...

This paper presents a novel application of tensegrity systems as lightweight and noninvasive braces for seismically resistant structures. The analyzed braces consist of D-bar systems equipped with shape memory alloy cables with superelastic response. These structures are able to markedly amplify the applied longitudinal displacements in the transve...

Full collection, visit also: https://www.hindawi.com/journals/ace/si/624623/

This ADAP 2019 Annual Issue follows and extends the ADAP Special Volume of 2018 and aims at providing a further insight into current trends and recent advancements in design and analysis, experimental testing, and modelling of protective structures.

Given their intrinsic features, adaptive facades are required to satisfy rigid structural performances, in addition to typical insulation, thermal and energy requirements. These include a minimum of safety and serviceability levels under ordinary design loads, durability, robustness, fire resistance, capacity to sustain severe seismic events or oth...

Shape memory alloys (SMA) present interesting functional characteristics (shape memory effect and superelasticity) that make them quite attractive for a wide range of applications. These functional characteristics are a consequence of phase transformations that take place within well-defined temperature ranges or stress ranges, depending on being t...

Adaptive facades are increasingly used in modern buildings, where they can take the form of complex systems and manifest their adaptivity in several ways. Adaptive envelopes must meet the requirements defined by structural considerations, which include structural safety, serviceability, durability, robustness and fire safety. For these novel skins,...

With a view to the development of a life-cycle approach to earth retaining walls, as well as an optimal management of the road assets as a whole, this paper presents a novel framework for the assessment of a large stock of earth retaining structures in a context of limited financial and human resources. In order to adequate the system for the numbe...

This paper studies the feasibility of using geodesic domes as expeditionary protective structures, since they are fast assembly lightweight structures and able to withstand very heavy loads due to their specific geometry. A 6 m standard ISO container is used as a benchmark structure for the study which is developed using the nonlinear explicit code...

Adaptive facades are getting more and more widespread in modern buildings. These facade systems, among many others, need to fulfil the requirements of several structural considerations, such as structural safety, serviceability, durability, robustness and fire safety, being typically defined for standard facades and building enclosures in general....

***** Buildings, Volume 8, Issue 10 (October 2018) ***** Our article "Dynamic Characterisation and Finite Element Updating of a RC Stadium Grandstand" has been selected as cover story of the volume 8 issue 10 of the journal Buildings! ***** http://www.mdpi.com/2075-5309/8/10

This paper reports on the dynamic characterisation of a Reinforced Concrete (RC) stadium grandstand module for the Sporting Stadium in Lisbon. To this aim, a three-dimensional (3D) Finite-Element (FE) numerical model, implemented according to the technical drawings of the structure, is first presented to provide preliminary estimates of the expecte...

Adaptive facades are getting more and more widespread in modern buildings. These facade systems, among many others, need to fulfil the requirements of several structural considerations, such as structural safety, serviceability, durability, robustness and fire safety, being typically defined for standard facades and building enclosures in general....

The objective of this ADAP Special Issue volume is to provide an overview on the current trends and recent advancements in terms of design and analysis, including experiments and modelling, on protective structures. ...

Glass has been overwhelmingly used for windows and facades in modern constructions, for many practical reasons, including thermal, energy, light and aesthetics. Nevertheless, due to the relatively low tensile strength and mostly brittle behaviour of glass, compared to other traditional materials, as well as to a multitude of interacting structural...

Shape-memory alloys are being progressively introduced as kernel components in seismic retrofitting devices for civil engineering structures. In order to control the instability associated with the first mechanical cycles, a training procedure is usually implemented, which stabilizes the superelastic behavior of the alloy. This paper addresses the...

Modern building envelopes are high-tech components that must meet requirements and constraints regarding architecture/urban planning/aesthetics, energy efficiency, indoor environmental quality, buildability and value. If a facade can respond to all the transient conditions while maintaining occupant satisfaction without imposing additional loads on...

Nowadays, the estimation of tensile forces in stay-cables or external tendons of Civil Engineering structures is required during periodic inspections. Among the available procedures, the ambient vibration testing (AVT) is recognized, in the scientific community, as an expedited technique. However, its accuracy is closely related to precise estimati...

This article explores the capabilities of a novel adaptive vibration absorber for civil engineering structures, with regard to frequency self-tuning, based on the temperature modulation of shape-memory alloy restitution elements. This real-time temperature modulation of shape-memory alloys, through Joule effect, enables to control the elastic modul...

SGAMR cover (In. J. Struct. Glass Adv. Mater Res.) https://thescipub.com/sgamr

Corrosion is the most deteriorating phenomenon causing structural deterioration of both prestressed and nonprestressed reinforced concrete structures. Precast and pretensioned concrete floor elements, as solid joists and solid and hollow-core planks, are widely used worldwide for structural floor of small to medium size buildings, including car-par...

In this study, the feasibility and potentiality of a novel design concept is explored by means of small scale experimental tests and Finite-Element numerical simulation. Taking advantage of the intrinsic potentiality of Shape-Memory Alloys wires able to work as adaptive actuators when subjected to joule heating, a 'smart-GFRP' concept consisting in...

Shape-memory alloys (SMAs) are a class of metal materials that exhibit two outstanding properties, namely the superelastic and the shape-memory effects. Taking advantage of these intrinsic properties, several applications have been proposed over the past years in robotic, automotive, and biomedical engineering in the form of SMA actuator wires and...

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 a...

Shape-Memory Alloys (SMAs) are a class of metal materials that exhibit two outstanding properties, the superelastic and the shape-memory effects. Taking advantage of these properties, several SMA actuator wires and plates have been proposed over the last years in robotic, automotive, and biomedical engineering. In this paper, the feasibility of a n...

Due to the growing application of laminated glass panels in building facades and roofs, tending towards the minimization of frameworks, substructures and supports, technological solutions based on the use of glass panels with increasingly wide dimensions and modern design principles are becoming more frequent. The growing use of structural glass ap...

This paper investigates the dynamic behaviour of cable-supported glazing facades 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...

ISBN 978-94-6186-581-6 Eds. A. Luible, M. Overend, L. Aelenei, U. Knaack, M. Perino, F. Wellershoff Publisher: TU Delft Open for the COST Action TU1403

This paper studies innovative restraining solutions based on lateral nickel-titanium (NiTi) shape-memory alloy (SMA) cables. Two novel control approaches are tested, which take advantage of superelasticity and the shape-memory effect. Superelasticity is employed in a passive control approach, using the restraining cables to increase the postbucklin...

Os sismos constituem uma das manifestações mais destrutivas e violentas da natureza, sendo responsáveis por inúmeras tragédias humanas, às quais estão associadas perdas económicas significativas. É possível estabelecer, a partir de experiências associadas a sismos já ocorridos, que os danos sísmicos podem assumir uma grande multiplicidade de formas...

Nowadays, modern analysis of civil engineering structures implies the use of increasingly sophisticated computer models, designed not only to predict the response of actual structures to different loadings, but also to simulate the effects of eventual modifications in their structural configuration. Nevertheless, it is often discovered that when th...

The design of a modern glass facade translates an architectural aspiration for transparency. Innovative technological solutions have made it possible to materialise a transparent planar surface, exploring the load-bearing capabilities of the glass itself. Facades also need to have back-up structures, which are designed to withstand seismic and wind...

SUMMARY The present paper presents a physical prototype that simulates the response of a single degree of freedom dynamic system, equipped with a novel semi-active vibration control device. This device comprises two superelastic NiTi elements working in phase opposition and aims to prevent deck unseating in simply supported bridges, during a seismi...

The proposed semi-active vibration control device originates from a passive control system, based on SE austenitic wires. In its semi-active version, the system monitors the feedback measurements and based on this information, continuously adjust the strain in the SE wires in order to improve its dynamical characteristics. The strain accumulation i...

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. The second model couples the mechanical and kinet...

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 mod...