The plates under study are treated with an unconstrained damping layer
which is applied either partially or throughout the plates. Several c
onfigurations of partial damping layer treatment has been studied and
in all the cases the volume of the damping material has been kept the
same. When such a plate is subjected to a harmonic excitation at one o
f the resonating frequencies the magnitude of the amplitude of vibrati
on and the dynamic stresses developed in the plate will depend mainly
on the damping ratio. The stresses in the damping layer depend on the
damping ratio and at the same time also on the thickness of the layer.
Three boundary conditions are considered and the force of excitation
is of a point harmonic type. The analysis is carried out for first two
modes of vibration.