This book contains a sampling of papers presented at the June 2-5, 2002 International Workshop on Bifurcations andamp; Instabilities in Geomechanics (IWBI 2002). The scope of the Workshop includes analytical approaches, numerical methods, and experimental techniques.

This is an up-to-date review of developments in the field of bifurcations and instabilities in geomechanics from some of the world’s leading experts. Leading international researchers and practitioners of the topics debate the developments and applications which have occurred over the last few decades. Beside fundamental research findings, applications in geotechnical, petroleum, mining, and bulk materials engineering are emphasised.

Geomaterials exhibit complex but rich mechanical behaviour with a variety of failure modes ranging from diffuse to localized deformation depending on stress, density, microstructure, and loading conditions. These failure modes are a result of an instability of material and/or geometric nature that can be studied within the framework of bifurcation theory. Degradation is another related phenomenon arising from cyclic loading, ageing, weathering, chemical attack, and capillary effects, among others. The methodology of analyzing the various types of instabilities is crucial in the adequate modelling and safe design of numerous problems in geomechanics. The present volume contains a sampling of enlarged versions of papers presented at the International Workshop on Bifurcation and Degradations in Geomaterials (IWBDG 2008) held in Lake Louise, Alberta, Canada, May 28-31, 2008. These papers capture the state-of-the-art in the specialized field of geomechanics and contemporary approaches to solving the central issue of failure. Some engineering applications are presented in the areas of energy resource extraction and soil-machine interaction.

This book examines the experimental and theoretical aspects of bifurcation analysis as applied to geomechanics. Coverage includes basic continuum mechanics for dry and fluid unfiltrated porous media, bifurcation and stability analyses applied to layered geological media and granular materials, and theories for generalized continua as applied to materials with microstructure and in relation to strain localization phenomena.

Instabilities Modeling in Geomechanics describes complex mechanisms which are frequently met in earthquake nucleation, geothermal energy production, nuclear waste disposal and CO2 sequestration. These mechanisms involve systems of non-linear differential equations that express the evolution of the geosystem (e.g. strain localization, temperature runaway, pore pressure build-up, etc.) at different length and time scales. In order to study the evolution of a system and possible instabilities, it is essential to know the mathematical properties of the governing equations. Therefore, questions of the existence, uniqueness and stability of solutions naturally arise. This book particularly explores bifurcation theory and stability analysis, which are robust and rigorous mathematical tools that allow us to study the behavior of complex geosystems, without even explicitly solving the governing equations. The contents are organized into 10 chapters which illustrate the application of these methods in various fields of geomechanics.

Solutions for soil engineering and soil-structure interaction problems need realistic and pertinent experimental and modelling tools. In this work, extensive developments proposed by the invited speakers of the Lyon International Symposium held in September 2003 are presented, including experimental investigations into deformation properties; laboratory, in-situ and field observation interpretations; behaviour characterisation and modelling; and case histories. The contributions include recent investigations into anisotropy and non-linearity, the effects of stress-strain-time history, ageing and time effects, yielding, failure and flow, cyclic and dynamic behaviour. In addition, advanced geotechnical testing is applied to real engineering problems, and to ways of synthesising information from a range of sources while engaging in practical site characterisation studies.

This work contains proceedings of a workshop on Bifurcation and Localisation Theory in Geomechanics, held in Perth, Australia in 1999. It covers a range of themes from classic civil engineering subjects to non-linear and non-unique geological phenomena.

This book contains the scientific contributions to the 11th International Workshop on Bifurcation and Degradation in Geomaterials (IWBDG) held in Limassol-Cyprus, May 21-25, 2017. The IWBDG series have grown in size and scope, since their inception 30 years ago in Germany, covering more and wider areas of geomaterials and geomechanics research including modern trends. The papers cover a wide range of topics including advances in instabilities, localized and diffuse failure, micromechanical, multiscale phenomena, multiphysics modeling and other related topics. This volume gathers a series of manuscript by brilliant international scholars who work on modern recent advances in experimental, theoretical and numerical methods. The theoretical and applied mechanics are linked successfully with engineering applications in traditional and in emerging fields, such as geomechanics for the energy and the environment. The quality of the contributed papers has benefited from the peer review process by expert referees. This book can be used as a useful reference for research students, academics and practicing engineers who are interested in the instability and degradation problems in geomaterials, geomechanics, geotechnical engineering and other related applications.

Progressive failure has been a classical problem in the field of geotechnical engineering and has attracted considerable attention in connection with slope stability and foundation problems. It is associated with strain localization or shear banding and is also related to damage in material structures. As knowledge of the progressive failure mechanism increases, it is now necessary to establish effective communications between researchers and engineers. The International Symposium on Deformation and Progressive Failure in Geomechanics provided an opportunity for discussing recent advances in this area. A total of 136 papers were contributed from 22 countries. As well as these, the symposium proceedings also contain 8 interim technical reports on the subject by the members of the Asian Technical Committee of the International Society for Soil Mechanics and Foundation Engineering and the Japanese Geotechnical Society National Committee on Progressive Failure in Geo-structures.

This book presents the most recents developments in the modelling of degradations (of thermo-chemo-mechanical origin) and of bifurcations and instabilities (leading to localized or diffuse failure modes) taking place in geomaterials (soils, rocks, concrete). Applications (landslides, rockfalls, debris flows, concrete and rock ageing, etc.) are discussed in detail.