Publications associées à Wave propagation in periodic buckled beams. Part II: Experiments

Short-term behavior of glass fiber-polymer composite bending-active elastica beam under service load application

Thomas Keller, Landolf-Giosef-Anastasios Rhode-Barbarigos, Tara Habibi

Bending-active elastica beam is a structural configuration that is based on the elastic deformation of an initially straight beam. This deformation occurs when horizontal displacements are applied to a sliding support, causing the beam to bend into an arch ...

2024

Modeling friction and wear using an adaptive discrete-continuum coupling

Manon Eugénie Voisin--Leprince

When two objects slide against each other, wear and friction occur at their interface. The accumulation of wear forms what is commonly referred to as a ``third-body''. Understanding third-body evolution has significant applications in industry, where contr ...

EPFL2024

Insights from an extensive triaxial testing campaign on a shale for comparative site characterization of a deep geological repository

Lyesse Laloui, Alessio Ferrari, Eleonora Crisci

Several boreholes were drilled for site comparison of a deep geological repository (DGR) in Northern Switzerland. The main target of the exploration program was the >100m thick Opalinus Clay, the designated host rock encountered at approximately 450 to 100 ...

Elsevier2024

Influence of model uncertainty and long term deformations in action effects calculation in reinforced concrete structures

Xhemsi Malja

Most codes of practice adopt a semi probabilistic design approach for the dimensioning and assessment of structures. Accordingly, structural safety is ensured by performing limit state verifications using design values determined with adequately calibrated ...

EPFL2024

Oblique streaming waves observed in multipactor-induced plasma discharge above a dielectric surface

Guang-Yu Sun, Haomin Sun

In a recent discovery (Wen et al 2022 Phys. Rev. Lett. 129 045001), streaming waves were found in multipactor-induced plasma discharges. However, due to the limitations of a 1D simulation setup, these waves displayed only transverse dynamics. In this lette ...

2024

Optothermal shaping of lamb waves with square and spiral phase fronts

Romain Christophe Rémy Fleury, Aleksi Antoine Bossart, Janez Rus

We introduce a Lamb-wave medium with tunable propagation velocities, which are controlled by a two-dimensional heating pattern produced by a laser beam. We utilized it to demonstrate that waves in an appropriately designed medium can propagate in the form ...

2024

Spatiotemporal energy‐density distribution of time‐reversed electromagnetic fields

Farhad Rachidi-Haeri, Marcos Rubinstein, Nicolas Mora Parra, Hamidreza Karami, Elias Per Joachim Le Boudec

Time reversal exploits the invariance of electromagnetic wave propagation in reciprocal and lossless media to localize radiating sources. Time-reversed measurements are back-propagated in a simulated domain and converge to the unknown source location. The ...

2024

3D printed large amplitude torsional microactuators powered by ultrasound

Mehdi Ali Gadiri, Mahmut Selman Sakar, Amit Yedidia Dolev, Junsun Hwang

Here, we introduce a design, fabrication, and control methodology for large amplitude torsional microactuators powered by ultrasound. The microactuators are 3D printed from two polymers with drastically different elastic moduli as a monolithic compliant me ...

2024

Toward Metantennas: Metamaterial-Based Antennas for Wireless Communications

Yuanyan Su

Antennas have historically been the most common electromagnetic (EM) technology for wireless communication systems. Antenna as hardware is entirely dependent on the EM properties of the materials used, mostly related to the permittivity and permeability. I ...

Ieee-Inst Electrical Electronics Engineers Inc2023

Lattice Green's function method for Atomistic/Continuum coupling

Ankit Gupta

Metal plasticity is an inherently multiscale phenomenon due to the complex long-range field of atomistic dislocations that are the primary mechanism for plastic deformation in metals. Atomistic/Continuum (A/C) coupling methods are computationally efficient ...

EPFL2023

Nanoindentation of embedded particles

Andreas Mortensen, Alejandra Inés Slagter, Joris Pierre Everaerts

We address the effect of elastic inhomogeneity on elastic modulus and hardness determinations made by depth-sensing indentations performed on individual particles embedded within a matrix of different elastic modulus. Finite element simulations and nanoind ...

SPRINGER HEIDELBERG2023

Deformation response of highly stretchable and ductile graphene kirigami under uniaxial and biaxial tension

Ye Wei, Yao Chen, Tong Guo

Kirigami, the ancient technique of paper cutting, has been successfully applied to enhance the stretchability and ductility of nanoscale graphene. However, existing experimentally realized graphene kirigami (GK) are created by introducing parallel cuts, ex ...

Amer Physical Soc2023

Scalable angular spectrum propagation

Felix Wechsler

Coherent field propagation is an essential computational tool in optics with applications ranging from computational optics and optical design to iterative field reconstructions. An improvement in the computational speed of current propagation methods is t ...

Optica Publishing Group2023

Optimization of elastic wave propagation in a reconfigurable medium by genetic algorithms with adaptive mutation probability

Romain Christophe Rémy Fleury, Janez Rus

We introduce a reconfigurable medium for the manipulation of elastic propagation properties of Lamb waves. It is based on a shape memory polymer (SMP) with temperature-dependent Young's modulus. Waves are excited by a laser pulse and detected by a laser vi ...

IOP Publishing Ltd2023

Nonlocally-resonant metamaterials

Aleksi Antoine Bossart

In this thesis, we unveil a third design path to manipulate elastic waves within architected media, distinct from the traditional phononic crystal and locally-resonant metamaterial concepts. The core innovation lies in the concept of nonlocal resonances, d ...

EPFL2023

Nonlinear interactions of ion acoustic waves explored using fast imaging decompositions

Fast camera imaging is used to study ion acoustic waves propagating azimuthally in a magnetized plasma column. The high-speed image sequences are analyzed using proper orthogonal decomposition and 2D Fourier transform, allowing to evaluate the assets and d ...

2023

A fully-coupled highly-parallelized geomechanical simulator for assessing induced seismicity

Jean-François Molinari, Guillaume Anciaux, Nicolas Richart, Brice Tanguy Alphonse Lecampion, Emil Gallyamov

Induced seismicity caused by anthropogenic modification of the subsurface effective stress state has been observed in a number of industrial applications -- from hydrocarbon extraction (e.g., Groningen [1]), drilling waste-water disposal (e.g., [2]) to the ...

2023

Long-distance coherent propagation of magnon polarons in a ferroelectric-ferromagnetic heterostructure

Jean-Philippe Ansermet, Haiming Yu, Peng Chen, Song Liu, Jilei Chen, Jianyu Zhang, Jinlong Wang, Yao Zhang

We experimentally demonstrate the coherent propagation of magnon polarons, the hybridized excitations formed by the coupling of spin waves and Rayleigh/Love surface acoustic waves, in a heterostructure consisting of ferroelectric BaTiO3 and ferromagnetic L ...

Amer Physical Soc2023

Microscopic Digital Image Correlation Analysis of Strain Distributions in Stainless Steel 316L Induced by Multiaxial Cyclic Loading

Elif Cansu Kursun

Fatigue damage in materials results in localized strain at the microstructural level. In many engineering components of the cooling circuits of nuclear power plants, where austenitic steels are used, the material experiences multiaxial cyclic loading, eith ...

EPFL2023

Mechanics of Physical Knots: From Filaments in Contact to Surgical Suturing

Paul Johanns

In this thesis, we study the mechanics of tight physical knots. Knots are omnipresent in surgery, climbing, and sailing, with disastrous consequences when the filament or the rope fails to perform its function. Even if the importance of mechanical analysis ...

EPFL2023