Laurent Vulliet

Lyesse Laloui, Laurent Vulliet, Georg Klubertanz

This study presents a numerical approach designed for material parameter identification for the coupled hydro-mechanical boundary value problem (BVP) of the piezocone test (CPTU) in normally and lightly overconsolidated clayey soils. The study is presented ...

Wiley-Blackwell2011

Numerical modeling of unsaturated porous media as a two and three phase medium : a comparison

A numerical simulation of the hydro-mechanical behaviour of an unsaturated porous medium is presented. The coupled hydro-mechanical model used is based on the continuum theory of mixtures and treats the unsaturated soil as a three phase porous medium (soli ...

1997

New basis for the constitutive modelling of aggregated soils

Natural and compacted soils are usually characterized by aggregation of particles. The mechanical behaviour of these materials depends on soil structure. The oedometric compression tests performed on aggregated samples presented here showed that these mate ...

Springer-Verlag2008

A combined neural network/gradient-based approach for the identification of constitutive model parameters using self-boring pressuremeter tests

Lyesse Laloui, Laurent Vulliet, Georg Klubertanz

This paper presents a numerical procedure of material parameter identification for the coupled hydromechanical boundary value problem (BVP) of the self-boring pressuremeter test (SBPT) in clay. First, the neural network (NN) technique is applied to obtain ...

2009

Identification of mechanisms for landslide type initiation of debris flows

The modelling of debris flow initiation in slopes is addressed in this paper. First, possible factors governing debris flow initiation are established. Then, a coupled hydro-mechanical model for deformable porous media with two pore fluids that is used to ...

2009

Behavior of a dual-purpose pile as foundation and heat exchanger [Comportement d'un pieu bi-fonction, fondation et échangeur de chaleur]

The behaviour of a pile subjected to thermo-mechanical loads was studied in situ with the aim of quantifying the thermal influence on the bearing capacity of heat exchanger piles. To accomplish this, a pile situated in a building under construction was equ ...

National Research Council Canada2003

Numerical modeling and neural networks to identify model parameters from piezocone tests: II. Multi-parameter identification from piezocone data

This paper completes the study presented in the accompanying paper, and demonstrates a numerical algorithm for parameter prediction from the piezocone test (CPTU) data. This part deals with a development of neural network (NN) models which are able to map ...

Wiley-Blackwell2012

Characterization of natural sand under complex dynamic loading

An experimental study, conducted with an advanced triaxial press, evaluates the effect of different loading paths on the dynamic behavior of natural Swiss sand. Emphasis is put on comparison between the dynamic parameters evaluated in a single loading (wit ...

Taylor & Francis Group2009

Optimization framework for calibration of constitutive models enhanced by neural networks

A two-level procedure designed for the estimation of constitutive model parameters is presented in this paper. The neural network (NN) approach at the first level is applied to achieve the first approximation of parameters. This technique is used to avoid ...

2009

Constitutive modeling of unsaturated aggregated soils

A coupled water retention-mechanical constitutive model for unsaturated aggregated soils is presented here. Based on the multi-scale experimental results, the model incorporates the inter-particle bonding, fabric and partial saturation effects in a single ...

2010

Elasto-plasticity of unsaturated soils : laboratory test results on a remoulded silt

Current models of the elasto-plastic behaviour of unsaturated soils contain important underlying assumptions that have not been tested due to a lack of adequate experimental data. To address this issue, the objective of this paper is to provide a comprehen ...

2006

Thermodynamics of Saturated and Unsaturated Soils

Lyesse Laloui, Laurent Vulliet, Fatiha Bouchelaghem

An understanding of the behaviour of saturated/unsaturated soils is important for the design and analysis of geostructures. In this paper a continuum approach based on a structured thermodynamic theory of mixtures developed by Svendsen & Hutter (1995), in ...

1998

Numerical model of miscible grout propagation in deformable saturated porous media

In an attempt to describe the basic phenomenon of grout propagation, a continuous model of miscible fluid displacement in deformable saturated porous media is proposed. In order to exhibit the relevance of the hydromechanical coupling during the mass trans ...

1999

Structural characterization of unsaturated aggregated soil

Despite the recent experimental studies of soil structure, a comprehensive understanding of the macroscopic response of a soil in relation to its structure has not yet been achieved. This lack of understanding reveals the need for further assessments of so ...

2010

Assessment of structural evolution of aggregated soil using neutron tomography

The advanced non-destructive method of neutron tomography, together with image analysis, is used to evaluate the structural evolution of an aggregated soil during one-dimensional compression tests. Aggregation of primary particles is a commonly observed ph ...

American Geophysical Union2008

Automated Digital Image Processing for Volume Change Measurement in Triaxial Cells

Aurelio Muttoni, Laurent Vulliet, Vincent Labiouse, Sylvain Plumey

An automated digital image processing technique is presented for the measurement of specimen volume change during triaxial testing. A digital camera is fixed at a constant distance from the triaxial cell. Pictures taken at various intervals are processed ( ...

2007

Considerations on the design of cut-and-cover tunnels

The communication shows an alternative for introducing soil-structure interaction in the analysis of cut-and-cover tunnels. An uncoupled method is illustrated through two examples representative of the situations found in practice. The main features of eac ...

ELU-ULS 2006 - Symposium international sur les états limites ultimes des ouvrages géotechniques2006

Behavior of Unsaturated Aggregated Soil in Oedometric Condition