3aSA14. The process of wave localization in elastic structures of infinite length.

Session: Wednesday Morning, December 4

Time: 11:35

Author: D. A. Indejtchev
Location: Inst. of Problems of Mech. Eng. Acad. of Sci. of Russia, St. Petersburg, 199178, Russia


This article is the first to classify the phenomenon of trapped modes initiation in elastic systems with mass--spring inclusions. Necessary and sufficient conditions for low- and high-frequency trapped modes were found. It is shown then that in elastic systems (beams, plates, shells) which are bounded by a continuous spectrum displaced from 0 and have mass inclusions, a discrete spectrum of natural frequencies occurs before the first boundary frequency. Trapping modes of oscillation corresponding to those frequencies possess a particularly pronounced local character in the inclusions region. The discrete spectrum displacement to the continuous spectrum axis and initiation of high-frequency trapped modes are accompanied by a phenomenon of traveling waves damping (antiresonance).

ASA 132nd meeting - Hawaii, December 1996