A spectral study of an infinite axisymmetric elastic layer
Chorfi, Lahcène
ESAIM: Mathematical Modelling and Numerical Analysis - Modélisation Mathématique et Analyse Numérique, Tome 35 (2001), p. 849-863 / Harvested from Numdam

Nous présentons ici une étude théorique des modes propres dans une couche élastique axisymétrique. La modélisation mathématique permet de ramener ce problème à l’étude spectrale d’une suite d’opérateurs A n , n, non bornés et autoadjoints dans un espace de Hilbert adéquat. On montre que le spectre essentiel de A n est un intervalle du type [γ,+[ et que, sous certaines conditions portant sur les coefficients du milieu, le spectre discret est non vide.

We present here a theoretical study of eigenmodes in axisymmetric elastic layers. The mathematical modelling allows us to bring this problem to a spectral study of a sequence of unbounded self-adjoint operators A n , n, in a suitable Hilbert space. We show that the essential spectrum of A n is an interval of type [γ,+[ and that, under certain conditions on the coefficients of the medium, the discrete spectrum is non empty.

Publié le : 2001-01-01
Classification:  35P15,  47A70,  73D30
@article{M2AN_2001__35_5_849_0,
     author = {Chorfi, Lahc\`ene},
     title = {A spectral study of an infinite axisymmetric elastic layer},
     journal = {ESAIM: Mathematical Modelling and Numerical Analysis - Mod\'elisation Math\'ematique et Analyse Num\'erique},
     volume = {35},
     year = {2001},
     pages = {849-863},
     mrnumber = {1866270},
     zbl = {0994.35100},
     language = {en},
     url = {http://dml.mathdoc.fr/item/M2AN_2001__35_5_849_0}
}
Chorfi, Lahcène. A spectral study of an infinite axisymmetric elastic layer. ESAIM: Mathematical Modelling and Numerical Analysis - Modélisation Mathématique et Analyse Numérique, Tome 35 (2001) pp. 849-863. http://gdmltest.u-ga.fr/item/M2AN_2001__35_5_849_0/

[0] A. Bamberger, Y. Dermenjian and P. Joly, Mathematical analysis of the propagation of elastic guided waves in heterogeneous media. J. Differential Equations 88 (1990) 113-154. | Zbl 0714.35045

[0] A. Bamberger, P. Joly and M. Kern, Propagation of elastic surface waves along a cylindrical cavity of arbitrary cross section. RAIRO Modél. Math. Anal. Numér. 25 (1991) 1-30. | Numdam | Zbl 0739.73009

[0] M. Bouchon and D.P. Schmitt, Full-wave acoustic logging in an irregular borehole. Geophysics 54 (1989) 758-765.

[0] L. Chorfi, Étude mathématique des modes guidés dans un milieu élastique à symétrie de révolution. RAIRO Modél. Math. Anal. Numér. 30 (1996) 299-342. | Numdam | Zbl 0852.73021

[0] D.J. Duterte, A.S. Bonnet-Ben Dhia and P. Joly, Mathematical analysis of elastic surface waves in topographic waveguides 9 (1999) 755-798. | Zbl 0946.74034

[0] G. Duvaut, Mécanique des milieux continus. Masson, Paris (1990).

[0] T. Kato, Perturbation Theory for Linear Operators. 2nd edn., Springer-Verlag, New York (1976). | MR 407617 | Zbl 0342.47009

[0] J. Miklowitz, The Theory of Elastic Waves and Wave Guides. North-Holland Publishing Company, Amsterdam, New York, Oxford (1980). | Zbl 0565.73025

[0] J.A. Nitsche, On Korn's second inequality. RAIRO Anal. Numér. 15 (1981) 237-248. | Numdam | Zbl 0467.35019

[0] B. Nkemzi and B. Heinrish, Partial Fourier approximation of the Lamé equation in axisymmetric domains. Math. Methods Appl. Sci. 22 (1999) 1017-1041. | Zbl 0932.65117

[0] M. Reed and B. Simon, Methods of Modern Mathematical Physics. IV Analysis of Operators. Academic Press, New York, San Francisco, London (1978). | MR 493421 | Zbl 0401.47001

[0] M. Schechter, Operator Methods in Quantum Mechanics. North-Holland Publishing Company, Amsterdam, New York, Oxford (1981). | MR 597895 | Zbl 0456.47012

[0] G. A. Winbow, Seismic sources in open cased boreholes. Geophysics 56 (1991) 1040-1050.