In this paper, a new constrained layer damping configuration is proposed for beams of circular cross section that may experience both bending and torsional vibrations. The `barberpole' configuration consists of narrow strips of damping treatment oriented at a pitch angle relative to lines parallel to the beam centerline. The individual damping strips may be continuous over the length of the beam, or periodically segmented along the strip length. A quasistatic analysis is developed to evaluate the effectiveness of the barberpole configuration for damping bending and torsional vibrations. It is shown that damping for both bending and torsion is attainable with the same damping treatment if the constraining layer strips are periodically segmented. It is also shown that for the pure bending problem, the unsegmented barberpole geometry provides an improvement in damping over unsegmented straight strips. At each crossing of the beam neutral plane, the constraining layer is free of extensional stress, which provides a `virtual segmentation' effect. This virtual segmentation provides an alternative to conventional segmentation of the damping layer when the more conventional approach is undesirable due to environmental or operational reasons.

Date Published: 5 May 1995
PDF: 12 pages
Proc. SPIE 2445, Smart Structures and Materials 1995: Passive Damping, (5 May 1995); doi: 10.1117/12.208901

Published in SPIE Proceedings Vol. 2445:
Smart Structures and Materials 1995: Passive Damping
Conor D. Johnson, Editor(s)