Torsional surface waves in a gradient-elastic half-space

Georgiadis, HG; Vardoulakis, I; Lykotrafitis, G

dc.contributor.author	Georgiadis, HG	en
dc.contributor.author	Vardoulakis, I	en
dc.contributor.author	Lykotrafitis, G	en
dc.date.accessioned	2014-03-01T01:15:56Z
dc.date.available	2014-03-01T01:15:56Z
dc.date.issued	2000	en
dc.identifier.issn	0165-2125	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/13841
dc.subject	Dispersion Curve	en
dc.subject	Exponential Decay	en
dc.subject	Free Surface	en
dc.subject	hankel transform	en
dc.subject	Layered Structure	en
dc.subject	Linear Elasticity	en
dc.subject	Material Properties	en
dc.subject	Surface Acoustic Wave	en
dc.subject	Surface Wave	en
dc.subject	Wave Propagation	en
dc.subject	Electric and Magnetic Fields	en
dc.subject	Shear Horizontal	en
dc.subject.classification	Acoustics	en
dc.subject.classification	Mechanics	en
dc.subject.classification	Physics, Multidisciplinary	en
dc.subject.other	ENERGY	en
dc.title	Torsional surface waves in a gradient-elastic half-space	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/S0165-2125(99)00035-9	en
heal.identifier.secondary	http://dx.doi.org/10.1016/S0165-2125(99)00035-9	en
heal.language	English	en
heal.publicationDate	2000	en
heal.abstract	The present work deals with torsional wave propagation in a linear gradient-elastic half-space. More specifically, we prove that torsional surface waves (i.e. waves with amplitudes exponentially decaying with distance from the free surface) do exist in a homogeneous gradient-elastic half-space. This finding is in contrast with the well-known result of the classical theory of linear elasticity that torsional surface waves do not exist in a homogeneous half-space. The weakness of the classical theory, at this point, is only circumvented by modeling the half-space as having material properties variable with depth (E. Meissner, Elastische Oberflachenwellen mit Dispersion in einem inhomogenen Medium, Vierteljahrsschrift der Naturforschenden Gesellschaft in Zurich 66 (1921) 181-195; I. Vardoulakis, Torsional surface waves in inhomogeneous elastic media, Internat. J. Numer. Anal. Methods Geomech. 8 (1984) 287-296; G.A. Maugin, Shear horizontal surface acoustic waves on solids, in: D.E Parker, G.A. Maugin (Eds.), Recent Developments in Surface Acoustic Waves, Springer Series on Wave Phenomena, vol. 7, Springer, Berlin, 1988, pp. 158-172), as a layered structure (Maugin, 1988; E. Reissner, Freie und erzwungene Torsionsschwingungen des elastischen Halbraumes, Ingenieur-Archiv 8 (1937) 229-245) or by considering couplings with electric and magnetic fields for different types of materials (Maugin, 1988). The theory employed here is the simplest possible version of Mindlin's (R.D. Mindlin, Micro-structure in linear elasticity, Arch. Rat. Mech. Anal. 16 (1964) 51-78) generalized linear elasticity. A simple wave-propagation analysis based on Hankel transforms and complex-variable theory was done in order to determine the conditions for the existence of the torsional surface motions and to derive dispersion curves and cut-off frequencies. Also, we notice that, up to date, no other generalized linear continuum theory (including the integral-type non-local theory) has successfully been proposed to predict torsional surface waves in a homogeneous half-space. (C) 2000 Elsevier Science B.V. All rights reserved.	en
heal.publisher	ELSEVIER SCIENCE BV	en
heal.journalName	WAVE MOTION	en
dc.identifier.doi	10.1016/S0165-2125(99)00035-9	en
dc.identifier.isi	ISI:000086536400003	en
dc.identifier.volume	31	en
dc.identifier.issue	4	en
dc.identifier.spage	333	en
dc.identifier.epage	348	en