The ALERT Geomaterials Workshop 2017 will be organized from Monday, 2nd October until Wednesday, 4th October in Aussois, France. It will include the following sessions:

SESSION 1 (2nd October):“Porous Media Mechanics from geomaterials to non-geological media”

Organizers:

• William G. Gray
• Bernhard Schrefler
• Claudio Tamagnini

Outline: The mechanics of porous media – sometimes referred to as “poromechanics” – deals with porous, multiphase materials whose behavior is significantly influenced by the pore fluids. One obvious and very important field of application of the mechanics of porous media is the study of natural and man-made geomaterials, from which the disciplines of soil mechanics, rock mechanics and applied geotechnical engineering have emerged. However, the fundamental concepts of poromechanics are also at the base of a number of disciplines as varied as geophysics, biomechanics, physical chemistry, agricultural engineering and materials science. Therefore, significant progress and mutual benefits can be achieved – and in some cases they have – from the mutual interactions among these disciplines in gaining understanding of the coupled mechanical, hydraulic, thermal, electrical and chemical processes which might occur in porous media under a very large spectrum of possible “loading” conditions. With this in mind, the main goal of the workshop is to bring together researchers involved in experimental, theoretical and numerical studies in various classical and emerging areas of poromechanics, with the objective of identifying common methodological aspects and potential synergies among them.

SESSION 2 (3rd October, half-day): “Must Critical State Theory for Granular Mechanics be Revisited?”

Organizers:

• Yannis F. Dafalias
• Gioacchino Viggiani

Outline: Critical State Theory (CST) constitutes the cornerstone of soil constitutive modeling framework. Its two conditions on critical stress ratio and critical void ratio, generalized to multiaxial space, are considered to be both necessary and sufficient for Critical State (CS) to occur and be maintained, and a plethora of soil constitutive models have been constructed obeying these two conditions at failure, thus describing what is known as Critical State Soil Mechanics (CSSM).

Yet, objections to the basic premises of CST have appeared, some time sporadically, other times in a more systematic way. For example the uniqueness of the Critical State Line (CSL), mainly of its projection on the void ratio-effective pressure e-p space, has been debated; or whether or not the fabric at CS is isotropic or anisotropic is discussed, and several other issues. The bottom line is that CST needs a more critical review and possibly reconsideration of the way it is being taught at Universities and applied in practice.

The objective of this workshop is to address exactly this critical and important issue of “correctness” or “completeness” of CST and the way it affects the teaching and application of CSSM. The format envisioned in order to address this objective, is to invite very few experts in this area of various backgrounds encompassing theoretical, experimental and numerical expertise, with a longer than usual presentation time each for a half day workshop with ample time for debate and questions and answers. The subject matter of challenging the paradigm of CST may turn out to be controversial because of its fundamental effect on geomechanics, but it is a necessary action to be taken by the geomechanics community. If nothing else, only positive results are expected, the major of which is the necessary critical thinking on the foundation of Soil Mechanics.

This session will be held by invited speakers only.

SESSION 3 (4th October): “Advanced numerical modelling of geomaterials with emphasis on large deformation and flow problems”

Organizers:

• Michael A. Hicks
• Pablo Mira
• Lorenzo Sanavia

Outline: Numerical modelling of geomaterials is still a challenging task, in particular when dealing with large deformation and flow problems, important for investigating a wide range of geotechnical applications. For example, in slope stability, these include debris flows, landslides, retrogressive failure, submarine slides and slope liquefaction, whereas, in soil-structure interaction, these include pile installation effects and proper interpretation of site investigation methods such as CPT. Traditional numerical tools, such as the finite difference and finite element methods, are often restricted to the modelling of slope failure initiation and soil-structure interaction at small strain, due to numerical problems such as mesh tangling in large deformation analysis. In recent years, this has led to the development of meshless, mesh free and other advanced numerical methods for tackling such problems. Moreover, numerical issues such as stability, convergence, locking and mass conservation properties are still open to new contributions.

This Workshop Session focusses on:

• The development of novel and robust methods of analysis for modelling geotechnical problems involving large deformation and flow.
• The application of these methods to investigate problems of practical and scientific interest.
• The evaluation of accuracy, robustness and efficiency of advanced numerical approaches.

The ALERT Workshop will be followed by the ALERT Doctoral School 2017 on Discrete Element Modelling.