Dynamics of Multibody Systems

In recent years there has been renewed interest in wave propagation in anisotropic elastic media because of current developments in composite materials and seismology.Although this book is written with emphasis on seismology, it will be of general interest also to those interested in understanding guided waves in laminated composite media.The book has seven chapters and five appendices.Its focus is on calculations of wave fields radiated by transient point sources in stratified anisotropic (and isotropic) media.It is assumed that the media are horizontally stratified such that each layer is a homogeneous anisotropic solid.Even in this context not all the methods that have been found useful in analyzing this problem are discussed.The aim of this monograph is to present the Cagniard-de Hoop technique combined with a generalized ray theoretic approach.Thus, it is rather narrow in its scope.Furthermore, no experimental results are presented.Even so, it gives a fairly thorough exposition of the generalized ray technique and the Cagniard-de Hoop method.So the book will be of use to those interested in analyzing and understanding pulse propagation in anisotropic media.The author lays out the scope of this book in the first chapter, which is followed by a general derivation in Chapter 2 of the generalized ray wave constituents in a stratified medium.Here the matrix formalism for expressing the motion-stress vector in any layer is succinctly developed.Chapter 3 deals with the source problem for a horizontally stratified isotropic medium.The general equations derived in Chapter 2 are specialized for the isotropic case in this chapter.Cagniard-de Hoop technique is illustrated in Chapter 4 by an application to the calculation of the transient wave field in an infinite isotropic medium due to a time dependent point source.Chapter 5 deals with the extension to transient motion in a stratified isotropic medium.Numerical results in the form of synthetic seismograms are presented for a four-layered case.Different source and receiver locations are considered.Finally, transient wave propagation in an unbounded homogeneous and a layered anisotropic medium is solved in Chapters 6 and 7, respectively.Numerical results are presented for transversely isotropic media.