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This paper deals with investigations on the active structural–acoustic control of a thin homogeneous isotropic plate using vertically reinforced 1-3 piezoelectric composite (PZC) material. A finite element model is developed for the plate which is integrated with a patch of active constrained layer damping (ACLD) treatment and coupled with an acoustic cavity to describe the coupled structural–acoustic behavior of the plate. The constraining layer of the ACLD treatment is composed of the vertically reinforced 1-3 PZC material. Both in-plane and out-of-plane actuations by the constraining layer of the ACLD treatment have been utilized for deriving the finite element model. An experiment is also carried out to investigate the performance of the patch of the ACLD treatment in which the constraining layer of the patch is made of vertically reinforced 1-3 PZC for active structural–acoustic control of the plate. Both the finite element analysis and the experimental investigation agree with each other and reveal that the vertically reinforced 1-3 PZC material performs excellently for achieving active structural–acoustic control of the isotropic plate.

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Dynamic cavitation is known to be a typical failure mechanism in rubber-like solids. While the mechanical behaviour of these materials is generally ratedependent, the number of theoretical and numerical works addressing the problem of cavitation using nonlinear viscoelastic constitutive models is scarce. It has been only in recent years when some authors have suggested that cavitation in rubber-like materials is a dynamic fracture process strongly affected by the rate-dependent behaviour of the material because of the large strains and strain rates that develop near the cavity. In the present work we further investigate previous idea and perform finite element simulations to model the dynamic expansion of a spherical cavity embedded into a rubber-like ball and subjected to internal pressure. To describe the mechanical behaviour of the rubber-like material we have used an experimentally calibrated constitutive model which includes rate-dependent effects and material failure. The numerical results demonstrate that inertia and viscosity play a fundamental role in the cavitation process since they stabilize the material behaviour and thus delay failure.