Construction of large civil engineering infrastructures commonly involves very large volumes of rockfill, constituted by a mix of sand, gravel and rock blocks, sometimes up to tens of millions of cubic meters or even more, as in highways or railway platforms, marine infrastructures or large rockfill dams.

Rockfill materials used in such embankment construction are rarely tested directly to determine their mechanical properties in laboratory, because of the size of the apparatuses required and corresponding costs and durations of such tests. As a result, in the body of design methods involving these materials, a large part is left to empirical extrapolation from past constructions.

In the engineering of large rockfill dams, this situation has led to serious technical accidents during commissioning on very high dams worldwide in the mid of years 2000, raising concern in the profession and promoting a move to more rational approaches in design, through structural analysis and relevant material testing. This highlights the need to improve our knowledge on the behavior of granular geomaterials constituting these infrastructures, as well as on the behavior of the structures themselves. A way for such improvement may be searched into better integration of physical local phenomena within the materials, up to the scale of the engineering structures.

The proposed paper, resulting from a long-term work into the physics of granular geomaterials, as well as into the engineering of large civil works, reviews and summarizes an attempt to move forward relevantly in that sense, proposing a new vision of mechanical behavior of these granular geomaterials, through an original micro-mechanical dissipative approach, detailed extensively in a recent book[1].

After a section on background and key assumptions, the paper begins on main theoretical features of dissipative structures induced by elementary contact friction, associated with specific statistical mechanics properties within granular materials in quasi-static motion, and their multi-scale expression into key tensor relations: the equations of energy dissipation resulting from contact friction.

These dissipation relations and related features constitute the backbone of practical applications developed further on in the paper, starting by a focus on strain localization and shear band detailed features, leading to the process of failure lines generation.

Then, next sections develop explicit practical applications of the main macroscopic energy-dissipation equation and related features, to a large set of key properties of great relevance in geotechnical and civil engineering, mainly:

- The Failure Criterion, resolving into Coulomb criterion under critical state, key to stability, retaining structures and bearing capacity questions;

- The relations between shear strength and volume changes, expressed in generalized 3D Stress-Dilatancy relations, resolving into classical Rowe's relations in particular conditions, key to shear strength features;

- The Characteristic state, a key to liquefaction phenomenon and its consequences;

- Cyclic Compaction features under alternate shear movements, widely used in materials improvement practice;

- The geostatic equilibrium (or earth pressure at rest coefficient K0), achieving a relation close to Jaky formula, key to the design of braced excavations, and shallow underground works;

A section is focused on a wide set of experimental data collected worldwide, covering most of experimental apparatuses, which validates in depth this dissipative approach of mechanical behavior.

Although most of the paper focusses on features induced by contact friction, a last section presents also key results on practical features resulting from particle breakage, the other main dissipative process after contact friction. These results include explicit incidences on size effects in shear strength, slope stability and safety factors, deformations and settlements in rockfill embankment dams.