Limit Analysis And Rheological Approach In Soil Mechanics

During the last ten years, our understanding of the perfect plasticity and the associated flow rule assumption on which limit analysis is based has increased considerably. Many extensions and advances have been made in applications of limit analysis to the area of soil dynamics, in particular, to earthquake-induced slope failure and landslide problems and to earthquake-induced lateral earth pressures on rigid retaining structures. The purpose of the book therefore is in part to discuss the validity of the upper bound work (or energy) method of limit analysis in a form that can be appreciated by a practicing soil engineer, and in part to provide a compact and up-to-date summary of recent advances in the applications of limit analysis to earthquake-induced stability problems in soil mechanics.

Developments in Geotechnical Engineering, Volume 7: Limit Analysis and Soil Plasticity covers the theory and applications of limit analysis as applied to soil mechanics. Organized into 12 chapters, the book presents an introduction to the modern development of theory of soil plasticity and includes rock-like material. The first four chapters of the book describe the technique of limit analysis, beginning with the historical review of the subject and the assumptions on which it is based, and then covering various aspects of available techniques of limit analysis. The subsequent chapters deal with the applications of limit analysis to what may be termed “classical soil mechanics problems that include bearing capacity of footings, lateral earth pressure problems, and stability of slopes. In many cases, comparisons of limit analysis solution and conventional limit equilibrium and slip-like solutions are also presented. Other chapters deal with the advances in bearing-capacity problem of concrete blocks or rock and present theoretical and experimental results of various concrete bearing problems. The concluding chapter examines elastic-plastic soil and elastic-plastic-fracture models for concrete materials. This book is an ideal resource text to geotechnical engineers and soil mechanics researchers.

Soil rheology is a branch of soil mechanics investigating the origin of, and the time-dependent changes in the stressed and strained state of soil. The author of this book however interprets rheology as being the science concerned on the one hand with how the state of stress and strain is formed and altered in a body, and on the other, with the particulars of the body's behaviour failing to fit the traditional concepts of elasticity and plasticity. There are many instances where the actual behaviour of soil differs substantially from schematized concepts and by taking into account all the peculiarities of soil deformation, precise knowledge of soil properties can be obtained and analytical prediction thus improved. Such problems are tackled in this book. This book comprises three main parts. The first part deals with basic rheological concepts and terms, the physics of soil, principles of stress-strain theory, elasticity, plasticity and viscosity - all cardinal rheological properties. The second part explains the rheological processes taking place in soils, such as creep and long-term strength, which are examined by the author with allowance for nonlinear deformation. Along with the known phenomenological theories, attention is paid to the novel kinetic (physical) theory of deformations and long-term strength. The third part outlines the generalized theory of soil deformation. It explains why soil offers different resistances to tensional and compressional deformations and derives the generalized rheological equation of state, enabling the effect of the three stress tensor invariants on the changes in shape and volume to be taken into account. From the standpoint of the theory discussed, the penultimate chapter gives examples of solutions to some problems facing soil mechanics. The final chapter reviews mathematical models representing the actual behaviour of soil under load and provides numerical solutions for engineering problems obtained with the aid of computer models. Thus the book provides a wealth of information which will be of interest both to the practising geotechnical engineer as well as to teachers and students.

This Book Brings Out The Possibilities Of Generalizations Of Behaviour Of Soils And Hence Of Predicting The Required Engineering Properties Without Elaborate Testing. We Recognize That A Single Approach Cannot Be Evolved For All Soil Types And Hence The Necessity For Classifying Soils Into Different Categories And To Use Appropriate Model For Each. First Of All, Based On Mechanism Of Stress Transfer And Interaction Between The Phases, Two Obvious Classes, The Fine Grained And Coarse-Grained Soils Have Been Differentiated.The Discussions Bring Out That Because Of Identical Mode Of Stress Transfer, The Mechanical Behaviour I.E., Compressibility, Shear Strength Relations, Permeability Variations Etc. Can Be Generalized For All Fine Grained Soils, Enabling The Prediction Of Behaviour Of Such Soils With Just The Knowledge Of Certain State And Index Properties. The Sequence Of Discussion Is On The Characterization Of Specific Soil States And Prediction Of Proportion Starting From The Ideal Saturated Uncemented Soils, Both Normally And Over Consolidated, Cemented Saturated Soils And Partly Saturated Soils.In Dealing With The Behaviour Of Coarse Grained Soils, The Importance Of Microfabric And The Difficulties In Possible Generalizations Are Discussed. Perhaps The Unique Feature Of This Book Is That The Division Of The Chapters Is Based On Different Soil States, All The Mechanical Behaviours Being Discussed Under Each Soil State.The Book Will Be Of Interest To Both Academicians And Practising Engineers, Researchers And Postgraduate Students. It Would Serve As A Textbook For Undergraduate Students With Prior Knowledge Of Basic Soil Mechanics.

This book establishes the equations of limit analysis and provides a complete theoretical basis for foundation capacity, slope stability, and earth pressure. It is divided into three parts, the first of which discusses the failure mode and fundamental equation of soil mass. The second part addresses the solution methods for limit analysis, including the characteristic line method, stress field method, limit equilibrium method, virtual work equation-based generalized limit equilibrium method and generalized limit equilibrium method for the surface failure mode. Lastly, the third part examines the application of the limit analysis theory to soil mass.