Publications associées à Hinges for origami-inspired structures by multimaterial additive manufacturing

Effect of mechanical nonlinearity on the electromagnetic response of a microwave tunable metamaterial

Taha Goudarzi, Romain Christophe Rémy Fleury, Bakhtiyar Orazbayev, Rayehe Karimi Mahabadi

Tunable metamaterials functionalities change in response to external stimuli. Mechanical deformation is known to be an efficient approach to tune the electromagnetic response of a deformable metamaterial. However, in the case of large mechanical deformatio ...

IOP Publishing Ltd2022

Oligomodal metamaterials with multifunctional mechanics

Aleksi Antoine Bossart

Mechanical metamaterials are artificial composites that exhibit a wide range of advanced functionalities such as negative Poisson's ratio, shape shifting, topological protection, multistability, extreme strength-to-density ratio, and enhanced energy dissip ...

National Academy of Sciences2021

Crack propagation in CFRP laminates under mode I monotonic and fatigue loads: A methodological study

John Botsis, Charlie Joseph Simon Blondeau, Georgios Pappas

Delamination in composite materials is often accompanied by fiber bridging that increases resistance to crack growth. Here, delamination of two unidirectional carbon/epoxy systems was studied under monotonic and displacement-controlled fatigue loading. One ...

ELSEVIER SCI LTD2021

Load history effects in fibre-reinforced polymer composite materials

Abdolvahid Movahedirad

Today, it is widely accepted that fatigue is one of the most common failure mechanisms in structural components, and pure static failure is rarely observed. Engineering structures are subjected to complex mechanical fatigue loading histories, which cause d ...

EPFL2019

Two-dimensional crack growth in FRP laminates and sandwich panels

Aida Cameselle Molares

Fiber-reinforced polymer (FRP) composite materials are currently being selected for the design of lightweight and efficient structural members in a wide number of engineering applications. Sandwich panels with glass fiber-reinforced polymer (GFRP) face she ...

EPFL2019

Experimental tests on the out-of-plane response of RC columns subjected to cyclic tensile-compressive loading

Katrin Beyer, João Saraiva Esteves Pacheco de Almeida, Angelica Rosso, Lisandro Arturo Jimenez Roa

Over the last few years the increasing demand of housing for low income population in Colombia and several neighboring countries, associated to the significant increase of cost of land, has prompted construction companies to build medium to high rise reinf ...

2017

Punching strength of continuous flat slabs

Jürgen Einpaul

Reinforced concrete slabs with uniform thickness are common in residential and commercial buildings but can also be found in other types of structures. Such slabs are susceptible to punching shear failures, where a supporting column penetrates through the ...

EPFL2016

Processing and damage recovery of intrinsic self-healing glass fiber reinforced composites

Véronique Michaud, Federica Sordo

Glass fiber reinforced composites with a self-healing, supramolecular hybrid network matrix were produced using a modified vacuum assisted resin infusion moulding process adapted to high temperature processing. The quality and fiber volume fraction (50%) o ...

Institute of Physics2016

Punching shear strength and behaviour of compact reinforced concrete footings

Aurelio Muttoni, Miguel Fernández Ruiz, João Tiago Ramos Bernardo de Santa Rita Simões

concrete footings with and without transverse reinforcement. Even though that punching shear failures have already been deeply investigated, there is still scanty experimental information on full-scale reinforced concrete footings failing in punching shear ...

11th fib International PhD Symposium in Civil Engineering2016

Post-wrinkling behavior of webs in GFRP cell-core sandwich structures

Thomas Keller, Behzad Dehghan Manshadi, Anastasios Vassilopoulos

Similarly to the post-buckling behavior of steel girder webs, the post-wrinkling behavior of glass fiber reinforced polymer (GFRP) cell-core sandwich webs can increase their ultimate shear strength. Post wrinkling is, however, different from post-buckling ...

Elsevier2016

Temperature effects on material properties and structural response of polymer matrix composites

Wei Sun

Structural components used in civil engineering applications are often subjected to compressive loads. Unlike the tensile strength of fiber-reinforced polymer (FRP) materials, their compressive strength is resin-dominated, exhibiting lower values and more ...

EPFL2015

Tetradymites as Natural Hyperbolic Materials for the Near-Infrared to Visible

Klaus Kern, Moritz Esslinger, Pascal Gehring

Hyperbolic media exhibit unparalleld properties, e.g, as light absorbers in photovoltaics and photonics, as superlenses in far-field imaging, as subwavelength light concentrators in nanolithography, or as novel materials in emission engineering. With the a ...

Amer Chemical Soc2014

Punching strength of actual two-way slabs

Aurelio Muttoni, Miguel Fernández Ruiz, Jürgen Einpaul

Many building codes rely on empirical formulations with respect to the punching shear design provisions. Such empirical equations are typically calibrated on the basis of laboratory tests performed on simplified geometries (usually isolated specimens) with ...

4th fib Congress, Mumbai2014

Structural performance of complex core systems for FRP-balsa composite sandwich bridge decks

Michael Osei-Antwi

Based on current fiber-reinforced polymer (FRP) composite construction principles, FRP decks fall into two categories: pultruded decks and sandwich decks. Sandwich decks comprise face sheets and either honeycombs or foams reinforced with internal FRP webs ...

EPFL2014

Analytical modeling of local stresses at Balsa/timber core joints of FRP sandwich structures

Julia De Castro San Roman Fest, Thomas Keller, Anastasios Vassilopoulos, Michael Osei-Antwi

In order to optimize sandwich structures, core materials of different density and thus different stiffness and strength are often combined. The material discontinuities at joints of dissimilar core materials may lead to abrupt changes of the shear angles a ...

Elsevier2014

Contribution to shear wrinkling of GFRP webs in cell-core sandwiches

Julia De Castro San Roman Fest, Thomas Keller, Behzad Dehghan Manshadi, Anastasios Vassilopoulos

Glass-fiber-reinforced polymer (GFRP) cell-core sandwiches are composed of outer GFRP face sheets, a foam core, and a grid of GFRP webs integrated into the core to reinforce the shear load capacity. One of the critical failure modes of cell-core sandwich s ...

American Society of Civil Engineers2011

A 1D elastic plastic damage constitutive law for bone tissue

Alain Curnier, Daniel Garcia

Motivated by applications in orthopaedic and maxillo-facial surgery, the mechanical behaviour of cortical bone in cyclic overloads at physiological strain rates is investigated. To this end, a new one-dimensional rate-independent constitutive model for com ...

2010

Piecewise non-linear constant life diagram formulation for FRP composite materials

Thomas Keller, Behzad Dehghan Manshadi, Anastasios Vassilopoulos

A new formulation for predicting an asymmetric, piecewise non-linear constant life diagram (CLD) is introduced in this paper. The development of the new model is based on the representation of the fatigue data on the stress ratio (R)-stress amplitude (σa) ...

Elsevier2010

Modeling of strength degradation for fiber-reinforced polymer composites in fire

Thomas Keller, Yu Bai

A model for predicting composite material strength degradation under elevated and high temperatures is proposed. This model is based on the morphology of the mixture of materials in different states. The degradation of resin-dominated shear strength can be ...

2009

Fiber reinforced polypropylene nanocomposites

Chrystèle Houphouet-Boigny Favre

The aim of this thesis is to assess the feasibility of integrating nanoparticles into glass fiber (GF) reinforced isotactic polypropylene (iPP) composites via existing thermoplastic processing routes, and to investigate whether this results in significant ...

EPFL2007