  This textbook in French describes the rheology of granular materials in the
quasi static regime at a macroscopic scale. It starts defining cohesion,
friction and the Coulomb approach, from the large-strain range. Then it focuses
on the range of small and intermediate deformation when the medium can dilate
if it is dense; different specific typical tests (oedometric, constant
pressure, constant volume) are defined, the behaviours they lead are carefully
described and their dependences upon initial density recalled. Roles of
friction and dilatancy are exemplified and their link with the deviatoric
stress too. "Natural" "phase space" is defined, which is (specific volume, mean
pressure, axial or deviatoric stress). Then the "critical" state, the
"characteristic" state and the Rowe's law of dilatancy are defined, and the
previous behaviours analysed in term of plastic deformation, showing that these
behaviours obey a specific rule of dissipation. An isotropic incremental
modelling is then proposed and studied, with a pseudo Poisson coefficient that
evolves with the stress ratio. It shows a good agreement with experimental
trends, while the theory keeps simple, which describes in particular the
isochoric compression and the oedometric compression correctly. Cyclic
behaviours are then described, and their link with soil liquefaction, with a
peculiar attention to the role of stress ratio. Basic concepts on micro-macro
passage are given, starting with a theoretical approach leading to an
exponential distribution of forces ; then it proposes a theory for the
compaction of the medium with pressure, that predicts the v-log(p) law for the
critical state.
