Random vibration of composite structures with an attached frequency-dependent damping layer

The paper presents an efficient and accurate random vibration method for composite laminated structures with an attached viscoelastic damping layer. The method accounts for both the Adams and Maheri type of damping of the structure and the frequency-dependent damping of the attached layer. For the resulting non-classically damped and frequency-dependent complex system, the method presented combines the pseudo excitation method (PEM) with both a real-mode-based degree-reduction scheme and a precise integration scheme. The method is: much more accurate than most methods in the literature because they ignore the frequency dependency of the damping; very efficient because PEM largely overcomes the time penalty caused by the very high number of modes which must be used; and mathematically equivalent to the CQC algorithm. Examples solved include the composite horizontal tail structure of an aircraft.