Prof. Gilles Pijaudier-Cabot, Laboratoire des fluides complex et leurs réservoirs, Université de Pau et des Pays de l’Adour, Anglet, France, on “What can be expected from lattice modelling of quasi-brittle materials?”,
on January 24, 2024, 3:00 p.m., HS 13 Ernst Melan, at the Vienna University of Technology.
Lattice modelling of quasi‐brittle materials such as concrete is a discrete, mesoscale, description of
the material in which constitutive relations are prescribed at a lower scale compared to the scale at
which continuum‐based constitutive relations are written usually. The meso‐structure of the
material is represented explicitly. Starting in the 1980’s, this approach has become more and more
popular, with two very different venues:
The first one stems from the physics of fracture in brittle disordered media. It relies on statistical
analyses. The purpose is to inform continuum‐based constitutive models on the nature of the
variables that govern the mechanical deformation. Two examples related to damage and coupled
hydromechanical effects are outlined.
The second venue started with the pioneering works of Cundall, Bazant and Zubelewicz, and Van
Mier in the 80’s. The mesoscale description of the material allows for upscaling. Complex nonlinear
responses at the macroscale are obtained, while keeping the constitutive model at the mesoscale
simple and less phenomenological compared to macroscale ones. Over the years, such lattice
models have become more and more efficient. In this lecture, we shall provide some examples
dealing with the prediction of structural size effect or hydraulic fracturing. These models can also
capture the complexity of the fracture process, as observed in experiments.
The superior capability of lattice approaches has a price: extensive computational cost in structural
analyses. Nevertheless, it can be expected that such models will be helpful to produce high‐fidelity
databases that could be readily used in modern data‐driven or coarse‐grained approaches. This
lecture concludes with recent results on coarse graining of results from the lattice discrete particle
model, allowing to reflect upon existing, nonlocal, macroscale models of failure.
Gilles Pijaudier‐Cabot graduated from Ecole Normale Supérieure de Cachan and obtained a doctoral
degree from université Pierre et Marie Curie in 1985 and a Ph.D. from Northwestern University in
1987. He joined CNRS in 1988 and later on the faculty of civil engineering of Ecole Normale
Supérieure de Cachan (ENSC) in 1992 as a full professor. At ENSC, he developed computational
tools for evaluating the integrity of concrete structures. In 1999, he joined Ecole Centrale de Nantes
and created with the help of Electricité de France, VM Matériaux and Lafarge, the Failure and
Durability group, jointly operated with industry. In 2007, Gilles Pijaudier‐Cabot moved to Université
de Pau et des Pays de l’Adour (UPPA) and directed the joint laboratory with CNRS and TOTAL on
complex fluids, geomechanics and geology. At UPPA, he has been in charge of the excellence
initiative of the university since 2017, serving today as a vice‐rector.
His research activities dealt first with damage mechanics. It was during his PhD with Prof. Z.P.
Bažant that the non‐local damage theory was coined, bridging the gap between continuum
mechanics and fracture mechanics in solid materials. Later on, he turned toward studies on the
physical aspects of fracture and durability mechanics, combining damage mechanics with chemistry
of cement. Starting in 2004, he focused interest on the permeation properties of concrete and
rocks undergoing mechanical loads, with applications to waste storage, safety of nuclear vessels,
and hydraulic fracturing for unconventional hydrocarbon production. He created in 2008 a group
dedicated to hydro‐mechanics of porous materials, including lattice approaches for failure,
analytical models for estimating multi‐phase fluid flow properties in rocks and coupled adsorption
and swelling phenomena in micro‐porous materials.
Gilles Pijaudier‐Cabot authored over 100 papers in international journals. He received the bronze
medal from CNRS in 1991 and the Jean Mandel prize of the French association of mechanics in 1992.
He has been a member of Institut Universitaire de France (IUF) since 1996. He obtained an ERC
advanced grant in 2008 and received the Dolomieu Grand Prix from the French Academy of
Sciences in 2019.
Member of ASCE‐EMD, and now EMI, Gilles Pijaudier‐Cabot has been the first foreign chair of a
technical committee of ASCE in 1997. He served as chairman of many committees at the national
level, and chaired the French national committee evaluating research on radioactive materials and
wastes for the past three years.