Ishibashi I., Hazarika H. Soil Mechanics. Fundamentals and Applications

2nd Ed. – CRC Press, 2015. – 420 p. – ISBN13: 978-1-4822-5042-8The book is written with the intention of providing a very basic yet essential concept of soil mechanics to students and engineers who are learning the fundamentals of soil mechanics for the first time. This book is meant mainly for college students who have completed key engineering science courses such as basic calculus, physics, chemistry, statistics, mechanics of solids, and engineering materials and are ready to enter into one of the specialty areas of civil, architectural, and geotechnical engineering. This book is intended to provide a thorough, fundamental knowledge of soil mechanics in a simple and yet comprehensive way, based on the students’ knowledge of the basic engineering sciences. Special emphasis is placed on giving the reader an understanding of what soil is, how it behaves, why it behaves that way, and the engineering significance of such behavior.
The organization of the new edition of the book (which includes the original 12 chapters) is as follows. Chapters and their contents are carefully placed in an order so that the understanding level of the subject matter increases gradually as we move from one chapter to another. Following the sequence presented in this book is therefore recommended.
After the introductory Chapter 1 about soil mechanics, Chapter 2 (Physical Properties of Soils) deals with the origin and the description of soils. The major terms used in soil mechanics are defined by using the three-phase diagram. Soil shapes and gradations are also discussed in this chapter. Chapter 3 (Clays and Their Behavior) presents unique characteristics of clays from their mineral origins, sizes, shapes, electrical properties, behavior in water, and interaction among particles. Based on this knowledge, their plastic behavior, swelling, and shrinkage properties, sensitivity, and quick clays are discussed.
Based on the information covered in Chapter 2 and Chapter 3, soil classifications by the Unified Soil Classification System (also ASTM) and by the American Association of State Highway and Transportation Officials (AASHTO) are presented in Chapter 4.
Chapter 5 handles laboratory and field compaction techniques, including description of relative density and the CBR (California Bearing Ratio) method.
Chapter 6 presents the flow of water through soils. Definitions of various hydraulic heads and the coefficient of permeability are presented, as well as the two dimensional flow net technique, introduced from a simple one dimensional water flow mechanism without using the Laplace equation. Finally, a systematic method to compute boundary water pressures is demonstrated.
In Chapter 7, the concept of effective stress and its applications to various important soil mechanics problems, including capillary rise, quicksand, and heave at the bottom of an excavation, are discussed. The concept is later used in consolidation theory (Chapter 9) and shear strength (Chapter 11).
Chapter 8 is a preparation chapter for Chapter 9 (Settlements). Stress increments in a soil mass due to various types of footing load on the ground are presented. Most of these solutions are based on Boussinesq’s elastic solution, and they are needed as the major source of consolidation settlements in Chapter 9.
In Chapter 9, Terzaghi’s one-dimensional consolidation theory and its application are presented. To simplify the discussions, the consolidation problems are categorized into two parts: “how soon” (rate) problems and “how much” (amount of final settlement) problems, so that readers can clearly avoid confusion while handling the thickness (H or 2H) of the clay layer.
Chapter 10 deals with Mohr’s circle, which is utilized in chapters relating to shear strength and lateral earth pressure. In particular, a clear definition of the shear stress sign convention is made so that the concept of the pole of Mohr’s circle (the origin of the planes) can be utilized effectively without any room for mistakes.
Chapter 11 is related to the shear strength of soils. Failure criteria are introduced, and laboratory as well as field shear strength determination techniques are presented. Clear definitions are presented on consolidated, unconsolidated, drained, and undrained shear strength parameters, and usages of these different shear strength parameters are critically evaluated.
In Chapter 12, at-rest earth pressure and the classic Rankine and Coulomb active and passive pressure theories are presented. These classic theories are critically reviewed in terms of their assumptions and limitations, and appropriate applications of the theories into practice are discussed.
Chapters 13 through 16 cover introductory foundation engineering. Chapter 13 is related to site exploration, which is needed prior to foundation design at given sites. It includes a site exploration program, geophysical methods, borehole drilling and sampling, and in-situ testing methods such as the standard penetration test, cone penetration test, and other field test procedures.
Chapter 14 first presents the bearing capacity theory and, as an application, the shallow foundation design procedure is described. Chapter 15 handles deep foundation design procedures. Various analytical and field pile foundation design procedures are presented. Negative skin friction, pullout resistance, group piles, and the consolidation settlement are also discussed.
Finally, in Chapter 16, slope stability problems are presented. The mechanism of slope failure, analytical methods for calculating the factor of safety, and slope stabilization principles are discussed.
In most of the chapters, many exercise problems were carefully selected for readers to practice the use of the learned concepts. Spreadsheet techniques are often employed in these exercise problems. At the end of each chapter, many problems are selected, and they can be utilized by students to further exercise their skills in problem solving, or they can be presented as homework assignments by instructors. Numerical values of solutions for the problem sections are shown at the end of the book for the convenience of self-study readers.