Accession Number : AD0019699


Title :   ASYMPTOTIC APPROXIMATION FOR THE ELASTIC NORMAL MODES IN A STRATIFIED SOLID MEDIUM


Corporate Author : AIR FORCE CAMBRIDGE RESEARCH LABS HANSCOM AFB MA


Personal Author(s) : Haskell, Norman A


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/019699.pdf


Report Date : Aug 1953


Pagination or Media Count : 23


Abstract : The asymptotic approximation method was applied to the calculation of normal modes of elastic waves in a solid medium. The approximations were based on the assumption that the properties of the medium are slowly varying functions of one coordinate in the sense of a small relative variation within a wave length. A comparison of dispersion curves computed by the approximate theory with those computed by the exact theory for a medium of 2 or 3 homogeneous layers indicated that the approximate theory is fairly accurate for normal modes of higher order than the fifth or sixth. The approximation for the lower modes is considered of some value for rough estimations, provided the approximations are used in conjunction with the limiting forms of the exact theory.


Descriptors :   *LAMINATES , *ELASTIC PROPERTIES , FREQUENCY , ESTIMATES , APPROXIMATION(MATHEMATICS) , ASYMPTOTIC SERIES , ELASTIC WAVES , ROUGHNESS , COORDINATES , VARIATIONS , SOLIDS , THEORY


Subject Categories : Laminates and Composite Materials
      Mechanics


Distribution Statement : APPROVED FOR PUBLIC RELEASE