Review of Dynamics of Structures: Theory and Applications to Earthquake Engineering, Third Edition, by Anil K. Chopra: Pearson Prentice-Hall, Upper Saddle River, N.J.; 2006; 876 pp.

Anil Chopra’s “Dynamics of Structures: Theory and Applications to Earthquake Engineering” has become the textbook of choice for courses on structural dynamics at many universities, both in the United States and abroad. It is an absolute must for a course on earthquake engineering with a rigorous theoretical component; I use it in my own course.

The reviews of the first edition of the book pointed out deservedly the rigor, breadth, and depth of the coverage, as well as the clarity of the exposition. The unusual combination of theoretical rigor with practical recommendations help lay emphasis on developing in the student a sound understanding of basic principles of structural behavior, providing simplified procedures to make initial estimates. Equally important is the large number of solved examples and problems. For a course on earthquake engineering, the book provides an excellent coverage of theoretical basics of seismic design but it needs to be complemented with additional reading and lectures.

The second edition of the book introduced significant additional, coverage of seismic design; seismic response of bridges, an important structure that receives limited, if any, attention in most books on structural dynamics; discussion of energy dissipation devices and base isolation as a means to reduce the earthquake excitation, and updates on various seismic codes.

The third edition incorporates further significant additions. In Chapter 6, a small but very significant addition is the presentation and discussion of the characteristics and response spectra of near-fault earthquakes in opposition to far-fault motions, illustrating clearly that not all earthquakes are created equal. This is a basic concept but often neglected. Chapter 7 includes one new figure (Fig. 7.11.1) illustrating the relation between ductility ratio and force reduction factor for the El Centro earthquake and for the median of 20 earthquakes. This figure helps one understand the basic rules to construct inelastic design spectra for different ductility ratios.

Chapter 19 has undergone major, if not complete, rewriting. It explains how structural models affect the results of dynamic analyses pointing out that some simple models can greatly overestimate the importance of dynamic P-Delta effects that are considerably reduced as the models are refined. The material in this chapter also clearly illustrates the lack of a simple and unique relationship between the ductility demands for a single degree of freedom system and the interstory ductility ratios of multistory frames, showing the difference in behavior between strong beam and strong column frames. An approximate procedure to estimate ductility demands in multistory frames is presented, assuming weak coupling between modes in the inelastic response and using static incremental analyses. The chapter discusses clearly the basic assumptions and limitations of various approximate procedures, clarifies the inelastic response of actual buildings, and dispels some commonly accepted but erroneous concepts. In my opinion, this material is essential to develop a sound understanding of the seismic response of buildings and the limitations of present practice.

Chapter 21 has updated the study and comparison of various codes (the 2006 version of the International Building Code, the 2005 National Building Code of Canada, the 2004 Code of the Federal District of Mexico and the 2004 version of the Eurocode 8). The comparison between requirements and the discussion of how these relate to basic concepts of dynamics is extremely valuable for structural designers.

Chapter 22 is a new introduction dealing with performance-based design and some of the approximate methods used in practice. Once again, as in Chapter 19, the material points out the limitations and ranges of validity of various procedures and suggests means to improve their usefulness. Although these are important observations, they are normally ignored. Their inclusion in a textbook, by someone with the credentials and reputation of Professor Chopra, makes one hope that they will be heeded.

Undoubtedly, the additions to the third edition increase the practical value of the book. In my opinion, this is not only a must as a textbook in a course on earthquake engineering (particularly at the graduate level), but also a necessary reference book in design offices and essential reading for professional seismic design engineers.