Geomechanical Modelling In Engineering Practice

The key to successful solution of problems by the finite element method lies in the choice of appropriate numerical models & their associated parameters for geological media. 16 invited contributions on: Basic concepts; Numerical modelling of selected engineering problems; Specific numerical models & parameters evaluation.

The key to successful solution of problems by the finite element method lies in the choice of appropriate numerical models & their associated parameters for geological media. 16 invited contributions on: Basic concepts; Numerical modelling of selected engineering problems; Specific numerical models & parameters evaluation.

The purpose of this book is to bridge the gap between the traditional Geomechanics and Numerical Geotechnical Modelling with applications in science and practice. Geomechanics is rarely taught within the rigorous context of Continuum Mechanics and Thermodynamics, while when it comes to Numerical Modelling, commercially available finite elements or finite differences software utilize constitutive relationships within the rigorous framework. As a result, young scientists and engineers have to learn the challenging subject of constitutive modelling from a program manual and often end up with using unrealistic models which violate the Laws of Thermodynamics. The book is introductory, by no means does it claim any completeness and state of the art in such a dynamically developing field as numerical and constitutive modelling of soils. The author gives basic understanding of conventional continuum mechanics approaches to constitutive modelling, which can serve as a foundation for exploring more advanced theories. A considerable effort has been invested here into the clarity and brevity of the presentation. A special feature of this book is in exploring thermomechanical consistency of all presented constitutive models in a simple and systematic manner.

Modeling in Geomechanics Edited by Musharraf Zaman The University of Oklahoma, USA Giancarlo Gioda Politecnico di Milano, Italy John Booker University of Sydney, Australia Geomechanics is an interdisciplinary field involving the study of natural and man-made systems with emphasis on the mechanics of various interacting phenomena. It comprises numerous aspects of engineering and scientific disciplines, which share common bases in mathematics, mechanics and physics. In recent years, with the extraordinary growth of computing power and resources, progress in the generation of new theories and techniques for the analysis of geomechanics problems has far surpassed their actual use by practitioners. This has led to a gap between our ability to deal with complex, inter-disciplinary problems in geomechanics and the actual impact of these advances on engineering practice. This book contains contributions from an international group of accomplished researchers and practitioners from various branches of soil and rock engineering, and presents the latest theoretical developments and practical applications of modeling in geomechanics. Chapters are grouped into four main sections: * Computational procedures * Constitutive modeling and testing * Modeling and simulation * Applications Efforts have been made to include recent developments and provide suggestions and examples as to how these can be applied in modeling actual engineering problems. Researchers, practitioners and students in geomechanics, mechanics of solids, soil and rock engineering will find this book an invaluable reference.

In geomechanics, existing design methods are very much dependent upon sophisticated on-site techniques to assess ground conditions. This book describes numerical analysis, computer simulation and modelling that can be used to answer some highly complex questions associated with geomechanics. The contributors, who are all international experts in the field, also give insights into the future directions of these methods. Numerical Analysis and Modelling in Geomechanics will appeal to professional engineers involved in designing and building both onshore and offshore structures, where geomechanical considerations may well be outside the usual codes of practice, and therefore specialist advice is required. Postgraduate researchers, degree students carrying out project work in this area will also find the book an invaluable resource.

Linear mathematical assumptions for procedures in other branches of engineering have little relevance for geoengineering, which must accommodate non-linear behaviors. Contributors to eight papers apply the breakthrough numerical modeling Distinct Element Method (Cundall, late 1960s). The design philosophy for structures or excavations in geotechnical engineering is different from that followed for fabricated materials like steel and concrete. The designer has little data both with regard to geological weaknesses and strength and deformation characteristics of materials before finalizing the designs. Also these characteristics vary from place to place. In-situ stresses due to gravity and tectonics and transient forces imposed due to rainfall and earthquakes make the matter more complicated. The pore waters carry the load initially before passing it on to the solids. For the analytical procedure, to be realistic, it should account for large displacements and non-linear behaviour including strain-softening. Because of these considerations, the designers have followed procedures based on simplifying assumptions such as linear, small strain, elastoplastic behaviour. Numerical procedures based on such assumptions, though very popular in other branches of engineering, have made little impact in geo-engineering. An attempt has been made in this book to compile the recent use of distinct element codes for solutions of some of the problems in geomechanics — particularly those involving excavations. It is hoped that it will provide an opportunity for the fraternity of geotechnical engineers to appreciate the opening of new frontiers in the use of computers for solving more challenging geotechnical problems.

Soil-structure interaction is an area of major importance in geotechnical engineering and geomechanics Advanced Geotechnical Engineering: Soil-Structure Interaction using Computer and Material Models covers computer and analytical methods for a number of geotechnical problems. It introduces the main factors important to the application of computer methods and constitutive models with emphasis on the behavior of soils, rocks, interfaces, and joints, vital for reliable and accurate solutions. This book presents finite element (FE), finite difference (FD), and analytical methods and their applications by using computers, in conjunction with the use of appropriate constitutive models; they can provide realistic solutions for soil–structure problems. A part of this book is devoted to solving practical problems using hand calculations in addition to the use of computer methods. The book also introduces commercial computer codes as well as computer codes developed by the authors. Uses simplified constitutive models such as linear and nonlinear elastic for resistance-displacement response in 1-D problems Uses advanced constitutive models such as elasticplastic, continued yield plasticity and DSC for microstructural changes leading to microcracking, failure and liquefaction Delves into the FE and FD methods for problems that are idealized as two-dimensional (2-D) and three-dimensional (3-D) Covers the application for 3-D FE methods and an approximate procedure called multicomponent methods Includes the application to a number of problems such as dams , slopes, piles, retaining (reinforced earth) structures, tunnels, pavements, seepage, consolidation, involving field measurements, shake table, and centrifuge tests Discusses the effect of interface response on the behavior of geotechnical systems and liquefaction (considered as a microstructural instability) This text is useful to practitioners, students, teachers, and researchers who have backgrounds in geotechnical, structural engineering, and basic mechanics courses.

In this fully up-to-date volume, important new developments and applications of discrete element modelling are highlighted and brought together for presentation at the First International UDEC/3DEC Symposium. Papers covered the following key areas: * behaviour of masonry structures (walls, bridges, towers, columns) * stability and deformation of tunnels and caverns in fractured rock masses * geomechanical modelling for mining and waste repositories * rock reinforcement design (anchors, shotcrete, bolts) * mechanical and hydro-mechanical behaviour of dams and foundations * rock slope stability, deformation and failure mechanisms * modelling of fundamental rock mechanical problems * modelling of geological processes * constitutive laws for fractured rock masses and masonry structures * dynamic behaviour of discrete structures. Numerical Modelling of Discrete Materials in Geotechnical Engineering, Civil Engineering, and Earth Sciences provides an ultra-modern, in-depth analysis of discrete element modelling in a range of different fields, thus proving valuable reading for civil, mining, and geotechnical engineers, as well as other interested professionals.