Publications associées à Hydro-mechanical analysis of volcanic ash slopes during rainfall

A Depth-Averaged Material Point Method for Shallow Landslides: Applications to Snow Slab Avalanche Release

Bertil Trottet, Johan Alexandre Philippe Gaume, Denis Aloyse Joseph Steffen, Lars Kristoffer Uhlen Blatny, Louis Marie Cédric Guillet

Shallow landslides pose a significant threat to people and infrastructure. Despite significant progress in the understanding of such phenomena, the evaluation of the size of the landslide release zone, a crucial input for risk assessment, still remains a c ...

AMER GEOPHYSICAL UNION2023

The influence of water-saturation on the strength of volcanic rocks and the stability of lava domes

Marie Estelle Solange Violay, Michael Heap

The rocks forming a volcanic edifice or dome are typically saturated or partially-saturated with water. However, most experiments aimed at better understanding the mechanical behaviour of volcanic rocks have been performed on dry samples, and therefore mos ...

2023

The Permeability of Porous Volcanic Rock Through the Brittle-Ductile Transition

Marie Estelle Solange Violay, Corentin Jean-Marie Rémi Noël, Gabriel Gérard Dominique Meyer, Michael Heap

The permeability of volcanic rock controls the distribution of pore fluids and pore fluid pressure within a volcanic edifice, and is therefore considered to influence eruptive style and volcano deformation. We measured the porosity and permeability of a po ...

2022

An unrefinement algorithm for planar THB-spline parameterizations

Annalisa Buffa

Unrefinement is a tool that allows to perform faster numerical simulations by controlling the level of precision in the specified area. We introduce an algorithm that creates a coarser geometry from an initial regular geometry, which is represented with re ...

ELSEVIER2022

Inception of Regular Valley Spacing in Fluvial Landscapes: A Linear Stability Analysis

Shashank Kumar Anand, Sara Bonetti

Incipient valley formation in mountainous landscapes is often associated with their presence at a regular spacing under diverse hydroclimatic forcings. Here we provide a formal linear stability theory for a landscape evolution model (LEM) representing the ...

2022

Efficient equilibrium-based stress recovery for isogeometric laminated curved structures

Pablo Antolin Sanchez, Alessandro Reali

This work extends the stress recovery for laminated composite solid plates, proposed in [1,2], to curved structures. Based on 3D Isogeometric Analysis (IGA) computations and equilibrium, this procedure uses a single element through the thickness in combina ...

ELSEVIER SCI LTD2021

Onset of sliding across scales: How the contact topography impacts frictional strength

Jean-François Molinari, Fabian Barras, Ramin Aghababaei

When two solids start rubbing together, frictional sliding initiates in the wake of slip fronts propagating along their surfaces in contact. This macroscopic rupture dynamics can be successfully mapped on the elastodynamics of a moving shear crack. However ...

AMER PHYSICAL SOC2021

Molecular simulations of interfacial systems: challenges, applications and future perspectives

Satoshi Takahama, Mária Lbadaoui-Darvas, Athanasios Nenes

We present a comprehensive review of methods and applications of molecular simulations of interfacial systems. We give a detailed overview of the main techniques and major challenges in the following aspects of solid and fluid surfaces: adsorption at solid ...

TAYLOR & FRANCIS LTD2023

Effective stress for unsaturated active clays and in-situ effective stress estimation methodology

Angelica Tuttolomondo

The complexity of the mechanics of active clays and, more generally, of geomaterials with clay minerals, under saturated and unsaturated conditions, still provides relevant scientific challenges today. Equally relevant challenges are the understanding of t ...

EPFL2021

The mechanical origin of snow avalanche dynamics and flow regime transitions

Betty Sovilla, Johan Alexandre Philippe Gaume, Xingyue Li

Snow avalanches cause fatalities and economic damage. Key to their mitigation is the understanding of snow avalanche dynamics. This study investigates the dynamic behavior of snow avalanches, using the material point method (MPM) and an elastoplastic const ...

COPERNICUS GESELLSCHAFT MBH2020

Modeling of TAE mode excitation with an antenna in realistic X-point geometry

Ambrogio Fasoli, Duccio Testa

Experimentally, it is observed that Toroidal Alfven Eigenmodes (TAEs) are difficult to excite with an external antenna when the plasma is in X-point geometry. Here, the effect of the X-point geometry on the efficiency of the TAE excitation with the externa ...

AMER INST PHYSICS2020

Variational phase-field continuum model uncovers adhesive wear mechanisms in asperity junctions

Jean-François Molinari, Sylvain Collet

Wear is well known for causing material loss in a sliding interface. Available macroscopic approaches are bound to empirical fitting parameters, which range several orders of magnitude. Major advances in tribology have recently been achieved via Molecular ...

2020

Mechanical Characterization of Integrally-Attached Timber Plate Structures: Experimental studies and macro modeling technique

Aryan Rezaei Rad

Spurred by the recent advancements in Computer-Aided Design (CAD), Integral Mechanical Attachment (IMA) technique has been resurrected. Using IMAs, connections between timber elements are established through their form, instead of using additional connecto ...

EPFL2020

Experimental study of impulse waves generated by viscoplastic fluid

Zhenzhu Meng

Landslide-generated waves, also called impulse waves, occur as a result of the intrusion of landslides (such as rock falls, debris flows, and avalanches) into bodies of water (such as lakes, reservoirs, and seas). The objective of this thesis was to study ...

EPFL2020

3D Boundary Element Simulation of Droplet Dynamics in Microchannels: How Droplets Squeeze Through Constrictions and Move in Electric Fields

Simon Sebastian Schütz

Flows of fluids with free surfaces show complex dynamical behavior. Examples include effects like capillary surface waves, topological transitions such as droplet breakup and coalescence, or pattern formation in wetting and de-wetting dynamics. These compl ...

EPFL2018

Pattern formation in thin liquid films: from coating-flow instabilities to microfluidic droplets

Gioele Mariano Nicolò Balestra

Nature and technical applications abound with thin viscous flows, ranging from the lava flow on volcanoes to the lubricating layer around confined bubbles in the microchannels of Lab-on-a-Chip devices. Countless are the examples where coating flows arise i ...

EPFL2018

Measurements of internal cracking in punching test slabs without shear reinforcement

Aurelio Muttoni, Miguel Fernández Ruiz, Jürgen Einpaul

Advancing the knowledge about the punching behaviour of flat slabs has been held back by the fact that only indirect measurements of the internal failure mechanism have typically been available. In this paper, a novel experimental approach for tracking the ...

2018

Dynamic behavior of rock during its post failure stage in SHPB tests

Xin Cai, Yang Zou, Yang Zhao

In order to investigate the micro-process and inner mechanism of rock failure under impact loading, the laboratory tests were carried out on an improved split Hopkinson pressure bar (SHPB) system with synchronized measurement devices including a high-speed ...

Elsevier Science Bv2017

From rock to magma and back again: The evolution of temperature and deformation mechanism in conduit margin zones

Marie Estelle Solange Violay, Michael Heap

Explosive silicic volcanism is driven by gas overpressure in systems that are inefficient at outgassing. The zone at the margin of a volcanic conduit-thought to play an important role in the outgassing of magma and therefore pore pressure changes and explo ...

Elsevier2017

The influence of through-thickness reinforcement geometry and pattern on delamination of fiber-reinforced composites: Part II - Modeling

John Botsis, Véronique Michaud, Georgios Pappas

This article reports modeling techniques and results based on experimental Mode I characterization of a layered woven GFRP material with tufting reinforcement. Standard tuft and loop-less geometries are investigated on three different areal patterns to eva ...

Elsevier2017