5R55. Scattering of Seismic Waves: Applications to the Mexico City Valley. - E Reinoso (Univ Nacional Autonoma, Mexico). WIT Press, Southampton, UK. 2002. 202 pp. ISBN 1-85312-833-3. $122.00.
Reviewed by CS Manohar (Dept of Civil Eng, Indian Inst of Sci, Bangalore, 560 012, India).
Amplification of seismic energy, as it filters through subsurface formations and mountainous terrain, is a complex dynamical phenomenon. From an engineering point of view, an understanding of this phenomenon is crucial in appreciating the spatial variability of ground motions and the concomitant damage patterns observed during strong motion earthquakes. Mathematical modeling of this phenomenon has become possible in the recent decades due to the developments in the field of computational solid mechanics and emergence of computing power. This book reports on such modeling efforts as applied to Mexico City valley with special emphasis on delineating the model predictions with observed earthquake amplification patterns. The book presents numerical models to predict the scattering from irregular topographies and alluvial valleys due to plane incident waves and Rayleigh waves. This book forms a part of a series on advances in earthquake engineering.
The book consists of eight chapters with a list of references following each chapter. The first chapter summarizes the contents of the book. The basics of linear elastodynamics and wave propagation in infinite media are covered in Chapter 2. The use of the boundary element method for 2D potential problems is detailed in Chapter 3. The problems of 2D and 3D elastodynamics are covered in Chapters 4 and 5. The material covered includes discussion on buried alluvial valleys (made up of two regions: half-space and the valley), canyons of arbitrary shapes, and scattering by mountains with arbitrary geometry. Chapter 6 summarizes the observed amplification patterns in the Mexico City valley. The author here concisely, yet comprehensively, summarizes the features discernable from earthquake accelerographs recorded since the 1985 Michoacan earthquake. In Chapter 7, the gamut of mathematical modeling tools outlined in Chapters 2–5 are brought to bear on the problem of modeling of Mexico City valley. Discussions on comparing observed facts with model predictions are made. While a 1D model is found to be adequate to explain most of the observed amplification, the need for adopting a 2D and 3D model is demonstrated to explain amplification at edges of the valley or when the clay deposits are deeper. The book concludes in Chapter 8 wherein a few suggestions for future research are also provided.
The book is well written and achieves well its stated objectives. The book contains ample references to published work. One of the striking features of this book has been the conception and outlay of the figures. This has added immensely to the eloquence of the book. This reviewer considers Scattering of Seismic Waves: Applications to the Mexico City Valley to be an excellent contribution to the literature on earthquake engineering. The book would serve as a valuable starting point for any efforts in mathematical modeling of seismic response of large valleys and mountains that house many cities of the world. The book qualifies to be a reference book that certainly would be a valuable addition to libraries of universities and research laboratories pursuing research and development in the areas of earthquake engineering and engineering seismology.