Publications by Alessandro Spadoni

Chat with Graph Search

Ask any question about EPFL courses, lectures, exercises, research, news, etc. or try the example questions below.

DISCLAIMER: The Graph Chatbot is not programmed to provide explicit or categorical answers to your questions. Rather, it transforms your questions into API requests that are distributed across the various IT services officially administered by EPFL. Its purpose is solely to collect and recommend relevant references to content that you can explore to help you answer your questions.

Nonlinear wave propagation in solids and material structures provides a physical basis to derive nonlinear canonical equations which govern disparate phenomena such as vortex filaments, plasma waves, and traveling loops. Nonlinear waves in solids however r ...

This paper presents a detailed study of the pressure waves and effective mechanical properties of a closed-cell cellular solid with entrained fluid. Plane-harmonic-waves are analyzed in a periodic square with a finite-element model of a representative-volu ...

A laser vibrometer is used to measure waves generated by a piezoelectric transducer in a solid steel sphere. The spatial and temporal resolution make it possible to verify the theoretical dispersion relation of spherical surface waves. In particular, the a ...

Low-frequency waves generated by an impact on an isostatic granular medium with vanishing confinement pressure are theorized to depend on rigid-particle collisions. According to this model, an impact generates a solitary wave spanning several particle diam ...

Finite deformations of planar slender beams for which shear strain can be neglected are described by the extensible-elastica model, where the strain-displacement relation is geometrically exact and the Biot stress–strain relation is linear. However, if the ...

Periodic buckled beams possess a geometrically nonlinear, load-deformation relationship and intrinsic length scales such that stable, nonlinear waves are possible. Modeling buckled beams as a chain of masses and nonlinear springs which account for transver ...

Wave propagation in pinned-supported, post-buckled beams can be described with the Korteweg de Vries (KdV) equation. Finite-element simulations however show that the KdV is applicable only to post-buckled beams with strong pre-compression. For weak and mod ...

Buckled periodic beams possess a geometrically nonlinear, load-deformation relation and intrinsic length scales such that stable, nonlinear waves are possible. In part I of this paper, a model has been derived that predict compressive/rarefaction, superson ...

Internal degrees of freedom and periodic structure are critical requirements in the design of acoustic/elastic metamaterials since they can give rise to extraordinary properties like negative effective mass and stiffness. However, they are challenging to r ...

This contribution is a summary of four lectures delivered by the first author at the CIME Summer school in June 2011 at Cetraro (Italy). Preparation of those lectures was greatly aided by the other authors of these lecture notes. Our goal is to present som ...

In the present paper, the performance of Biot's theory is investigated for wave propagation in cellular and porous solids with entrained fluid for configurations with well-known drained (no fluid) mechanical properties. Cellular solids differ from porous s ...

Numerical investigation of wave propagation in a cellular solid with closed cells configuration and entrained fluid showed an existence of two types of pressure waves, which have opposite polarization and have different phase and group velocities. This is ...

Wave propagation in granular solids is found to have at least two regimes: a low-frequency ballistic signal and a high-frequency diffusive tail. The latter is attributed to granules clapping or elastic waves within the granules themselves. The low frequenc ...

The physical mechanism of elastic wave propagation through granular solids is investigated. Based on the symmetry of a one dimensional chain of spheres, spherical surface waves are considered to be responsible for the energy transport. A simple mathematica ...

Auxetic materials expand when stretched, and shrink when compressed. This is the result of a negative Poisson's ratio ν. Isotropic configurations with ν≈−1 have been designed and are expected to provide increased shear stiffness G. This assumes that Young' ...

Bloch theorem provides a useful tool to analyze wave propagation in periodic systems. It has been widely used in physics to obtain the energy bands of various translationally-periodic cristals and with the advent of nanosciences like nanotubes, it has been ...

The chiral lattice is a unique structural network not symmetric to its mirror image, and with a negative Poisson’s ratio. Previous investigations have considered this structural network for the design of superior structural components with sandwich constru ...

Alessandro Spadoni

Chat with Graph Search

Low-frequency wave propagation in post-buckled structures

Elasto-Dynamic Behavior of a Two-Dimensional Square Lattice With Entrained Fluid II: Microstructural and Homogenized Models

Frequency-dependent, near-pole behavior of acoustic surface waves on a solid sphere

Intra-particle dynamics and the impact response of granular chains

Isogeometric rotation-free analysis of planar extensible-elastica for static and dynamic applications

Wave propagation in periodic buckled beams. Part I: Analytical models and numerical simulations

Wave dispersion in periodic post-buckled structures

Wave propagation in periodic buckled beams. Part II: Experiments

Closed-cell crystalline foams: Self-assembling, resonant metamaterials

Continuous Decompositions and Coalescing Eigenvalues for Matrices Depending on Parameters

Elastodynamics of a Two-Dimensional Square Lattice With Entrained Fluid-Part I: Comparison With Biot's Theory

Elasto-Dynamic Behavior Of A 2D Square Lattice With Entrained Fluid

The role of Rayleigh Waves in Granular Solids

Energy Transmission through Grain-to-grain Contacts: the Role of Bulk and Rayleigh Waves

Elasto-static micropolar behavior of a chiral auxetic lattice

Bloch Theorem With Revised Boundary Conditions Applied To Glide Plane And Screw Axis Symmetric, Quasi-One-Dimensional Structures

An Isotropic Auxetic Structural Network with Limited Shear Stiffness