Advanced Soil Mechanics

What’s New in the Fourth Edition: The fourth edition further examines the relationships between the maximum and minimum void ratios of granular soils and adds the American Association of State Highway and Transportation Officials (AASHTO) soil classification system. It summarizes soil compaction procedures and Proctor compaction tests. It introduces new sections on vertical stress due to a line load of finite length, vertical stress in Westergaard material due to point load, line load of finite length, circularly loaded area, and rectangularly loaded area. The text discusses the fundamental concepts of compaction of clay soil for the construction of clay liners in waste disposal sites as they relate to permeability and adds new empirical correlations for overconsolidation ratio and compression index for clay soils. It provides additional information on the components affecting friction angle of granular soils, drained failure envelopes, and secant residual friction angles of clay and clay shale. Contains 11 chapters Provides new example problems Includes SI units throughout the text Uses a methodical approach The author adds new correlations between field vane shear strength, preconsolidation pressure, and overconsolidation ratio of clay soils. He also revises and expands information on elastic settlement of shallow foundations, adds a precompression with sand grains, and presents the parameters required for the calculation of stress at the interface of a three-layered flexible system. An ideal resource for beginning graduate students, the fourth edition of Advanced Soil Mechanics further develops the basic concepts taught in undergraduate study by presenting a solid foundation of the fundamentals of soil mechanics. This book is suitable for students taking an introductory graduate course, and it can also be used as a reference for practicing professionals.

Table of Contents:
Soil aggregate, plasticity, and classification Introduction Soil: Separate size limits Clay minerals Nature of water in clay Repulsive potential Repulsive pressure Flocculation and dispersion of clay particles Consistency of cohesive soils Liquidity index Activity Grain-size distribution of soil Weight–volume relationships Relative density and relative compaction Relationship between emax and emin Soil classification systems Compaction Empirical relationships for proctor compaction tests References Stresses and strains: Elastic equilibrium Introduction Basic definition and sign conventions for stresses Equations of static equilibrium Concept of strain Hooke’s law Plane strain problems Equations of compatibility for three-dimensional problems Stresses on an inclined plane and principal stresses for plane strain problems Strains on an inclined plane and principal strain for plane strain problems Stress components on an inclined plane, principal stress, and octahedral stresses: Three-dimensional case Strain components on an inclined plane, principal strain, and octahedral strain: Three-dimensional case Stresses and displacements in a soil mass: Two-dimensional problems Introduction Vertical line load on the surface Vertical line load on the surface of a finite layer Vertical line load inside a semi-infinite mass Horizontal line load on the surface Horizontal line load inside a semi-infinite mass Uniform vertical loading on an infinite strip on the surface Uniform strip load inside a semi-infinite mass Uniform horizontal loading on an infinite strip on the surface Triangular normal loading on an infinite strip on the surface Vertical stress in a semi-infinite mass due to embankment loading References Stresses and displacements in a soil mass: Three-dimensional problems Introduction Stresses due to a vertical point load on the surface Deflection due to a concentrated point load at the surface Horizontal point load on the surface Vertical stress due to a line load of finite length Stresses below a circularly loaded flexible area (uniform vertical load) Vertical displacement due to uniformly loaded circular area at the surface Vertical stress below a rectangular loaded area on the surface Deflection due to a uniformly loaded flexible rectangular area Stresses in a layered medium Vertical stress at the interface of a three-layer flexible system Vertical stress in Westergaard material due to a vertical point load Solutions for vertical stress in Westergaard material Distribution of contact stress over footings Reliability of stress calculation using the theory of elasticity References Pore water pressure due to undrained loading Introduction Pore water pressure developed due to isotropic stress application Pore water pressure parameter B Pore water pressure due to uniaxial loading Directional variation of Af Pore water pressure under triaxial test conditions Henkel’s modification of pore water pressure equation Pore water pressure due to one-dimensional strain loading (oedometer test) References Permeability Introduction Darcy’s law Validity of Darcy’s law Determination of coefficient of permeability in the laboratory Variation of coefficient of permeability for granular soils Variation of coefficient of permeability for cohesive soils Directional variation of permeability in anisotropic medium Effective coefficient of permeability for stratified soils Determination of coefficient of permeability in the field Factors affecting the coefficient of permeability Electroosmosis Seepage Introduction Equation of continuity Use of continuity equation for solution of simple flow problem Flow nets Hydraulic uplift force under a structure Flow nets in anisotropic material Construction of flow nets for hydraulic structures on nonhomogeneous subsoils Numerical analysis of seepage Seepage force per unit volume of soil mass Safety of hydraulic structures against piping Filter design Calculation of seepage through an earth dam resting on an impervious base Plotting of phreatic line for seepage through earth dams Entrance, discharge, and transfer conditions of line of seepage through earth dams Flow net construction for earth dams References Consolidation Introduction Theory of one-dimensional consolidation Degree of consolidation under time-dependent loading Numerical solution for one-dimensional consolidation Standard one-dimensional consolidation test and interpretation Effect of sample disturbance on the e versus log σ′ curve Secondary consolidation General comments on consolidation tests Calculation of one-dimensional consolidation settlement Coefficient of consolidation One-dimensional consolidation with viscoelastic models Constant rate-of-strain consolidation tests Constant-gradient consolidation test Sand drains Numerical solution for radial drainage (sand drain) General comments on sand drain problems References Shear strength of soils Introduction Mohr–Coulomb failure criterion Shearing strength of granular soils Critical void ratio Curvature of the failure envelope General comments on the friction angle of granular soils Shear strength of granular soils under plane strain conditions Shear strength of cohesive soils Unconfined compression test Modulus of elasticity and Poisson’s ratio from triaxial tests Friction angles φ and φult Effect of rate of strain on the undrained shear strength Effect of temperature on the undrained shear strength Stress path Hvorslev’s parameters Relations between moisture content, effective stress, and strength for clay soils Correlations for effective stress friction angle Anisotropy in undrained shear strength Sensitivity and thixotropic characteristics of clays Vane shear test Relation of undrained shear strength (Su) and effective overburden pressure (p′) Creep in soils Other theoretical considerations: Yield surfaces in three dimensions Experimental results to compare the yield functions References Elastic settlement of shallow foundations Introduction Elastic settlement of foundations on saturated clay (Poisson’s ratio ν =0.5 ) Elastic settlement of foundations on granular soil Settlement calculation of foundations on granular soil using methods based on observed settlement of structures and full-scale prototypes Semi-empirical methods for settlement calculation of foundations on granular soil Settlement derived from theory of elasticity References Consolidation settlement of shallow foundations Introduction One-dimensional primary consolidation settlement calculation Skempton–Bjerrum modification for calculation of consolidation settlement Settlement calculation using stress path Comparison of primary consolidation settlement calculation procedures Secondary consolidation settlement Precompression for improving foundation soils Precompression with sand drains References Appendix Index

About the Author :
Professor Braja Das served as dean of the college of engineering and computer science at California State University Sacramento, and is the author of several geotechnical engineering texts and reference books.

Review :
"...an excellent introduction to advanced concepts of soil mechanics...easy to follow by students and practising engineers dealing with solutions to geotechnical problems..." -Dr Sanjay Kumar Shukla, Edith Cowan University, Perth, Australia "The concepts have been explained in lucid manner which is of great value to students at undergraduate and postgraduate levels. It is a true asset for faculty and the research workers." -Dr. Priti Maheshwari, Indian Institute of Technology Roorkee