11R25. Intermediate Mechanics of Materials. - JR Barber (Dept of Mech Eng and Appl Mech, Univ of Michigan, Ann Arbor MI). McGraw-Hill, New York. 2000. 594 pp. ISBN 0-07-232519-4. $102.95.
Reviewed by A Cardou (Dept of Mech Eng, Laval Univ, Quebec PQ, G1K 7P4, Canada).
As the title indicates, the present book is designed for those students who have already taken an introductory course in the mechanics (or strength) of materials. Thus, it covers material presented typically, in many undergraduate engineering curricula, in an elective course.
A number of excellent textbooks are already available for such courses and are usually titled “Advanced Mechanics of Materials” or “Advanced Strength of Materials,” not to mention those dealing mainly with structures, or even aircraft structures, which, in fact, cover more or less the same material.
Barber’s book is original in the sense that the subject matter is presented in a design perspective, even if it is restricted to simple solids, mostly beams, but also cylinders, disks, and cylindrical shells. A difference with design books is that basic stress, strain and strength concepts, and hypotheses are explained very thoroughly. However, mathematics are kept as simple as possible. In fact, no partial differential equation (PDE) is to be found in the book. Thus, while “Advanced Mechanics of Materials” books include several chapters which are an introduction to the Theory of Elasticity, in the present book, all differential equations are ordinary (ODE). The only partial differentiations occur in the context of energy principles (Rayleigh-Ritz and Castigliano). This may be the reason for the word Intermediate in the title.
Chapter 1 (Introduction) includes a review of elementary notions on stress, strain, and beams. It also includes considerations on the design process and in which perspective calculations should be performed. Chapter 2 (Material Behavior and Failure) covers usual material failure criteria, either for ductile failure, brittle fracture, or fatigue. The basic principles of Linear Elastic Fracture Mechanics (LEFM) are also presented. Chapter 3 (Energy Methods) presents the work-energy principle and its applications: Rayleigh-Ritz method and Castigliano’s theorems.
In Chapter 4 (Unsymmetrical Bending), the author presents the unsymmetrical bending of beams in the elastic domain, while Chapter 5 (Non-Linear and Elastic-Plastic Bending) is devoted to nonlinear and elastic-plastic bending of beams, including springback, residual stress, and limit load analysis. Chapter 6 (Shear and Torsion of Thin-Walled Beams) presents the basic theory of thin-walled beams under shear force and torsion. Closed (including multicell) and open sections are considered. Calculations are restricted to shear flow and twist angle. In Chapter 7, Beams on Elastic Foundations are analyzed in the case of a Winkler foundation.
In Chapter 8 (Membrane Stresses in Axisymmetric Shells), beam problems are set aside to consider axisymmetric shells under axisymmetric loads, allowing the calculation of meridional and circumferential membrane stresses. Axisymmetric Bending of Cylindrical Shells is studied in Chapter 9, where its basic equation draws on the ODE derived in Chapter 7.
Chapter 10 (Thick-Walled Cylinders and Disks) covers disks and cylinders in plane stress or strain, under axisymmetric loading (pressure, centrifugal forces, thermal stresses). The elastoplastic case (elastic-perfectly plastic), including residual stress calculations, is also considered. Chapter 11 (Curved Beams) returns to beam problems with the theory of curved beams. Finally, Elastic Stability is covered in Chapter 12, mostly in the context of beam bucking. An energy approach is used to obtain approximate solutions. Axisymmetric buckling of cylindrical shells is also studied, and the corresponding equation is shown to apply to the problem of rotating shaft whirling.
In Appendix A (The Finite Element Method), the basic principles of the FEMs are presented. Calculation of the stiffness matrix is detailed for one-dimensional elements (bars and beams). Appendix B (Properties of Areas) shows how to calculate the geometrical properties of areas while Appendix C (Stress Concentration Factors) gives a selection of stress concentration factor curves. Appendix D gives the answers to the even-numbered problems from the list that follows each chapter.
Each chapter contains several solved examples and ends up with a large collection of problems. Both the American and SI unit systems are used in those problems with numerical data, and as mentioned above, answers to even-numbered problems are given. Each chapter also gives a number of references for further reading. The book ends with a detailed subject index. Overall presentation, as well as figure quality are adequate. Notations and symbols follow North-American standards.
In summary, Intermediate Mechanics of Materials succeeds remarkably relative to the author’s stated aim and, with its emphasis on a design approach of this subject, the book is a very welcome addition to the list of currently available textbooks for second-level undergraduate courses on the mechanics of materials. With its insightful explanations and intermediate mathematical presentation, it should also prove useful for self-study to practicing engineers.