Surface-bonded piezoelectric actuators can be used to generate Rayleigh wave for monitoring surface damages of structures. This paper provides an analytical and numerical study to simulate the wave propagation in an elastic half plane with surface-bonded piezoceramic actuators under high-frequency electric loads. Based on a one dimensional actuator model, the wave propagation induced by a single actuator is studied first by using integral transform method and solving the resulting integral equations. The single actuator solution is then implemented into a Pseudo-incident wave method to study the wave propagation induced by multiple actuators. Two aspects of the work are examined. The first is concerned with the determination of the effect of the geometry, the material mismatch and the loading frequency upon the resulting waveform, while the second is concerned with the effect of the interaction between actuators upon the induced wave propagation.

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Surface-bonded piezoelectric sensors can be used to monitor the mechanical behavior of structures for damage detection. This article provides a comprehensive theoretical study of the dynamic coupling between a surface piezoelectric sensor and an elastic half-plane. Attention is focused on the transformation of mechanical deformation into electric signals under dynamic loads. The effect of the longitudinal stiffness of the sensor is included in the developed sensor model. The problem is then formulated by using Fourier transform and solving the resulting integral equations in terms of the interfacial stress. The accuracy of the developed sensor model is evaluated by comparing with results from the finite element analysis. Numerical simulation is conducted to study the relation between the sensor response and the deformation of the host medium under static and dynamic loads. The results indicate the significant effects of the geometry of the sensor, the material mismatch of the system, and the loading frequency upon the sensor response.

This paper provides an theoretical analysis of the properties of fibre reinforced composite materials under antiplane waves. A self-consistent scheme is adopted in calculating the effective material constants. A new averaging technique is developed to account for the effects of the waveform. The model is then used to evaluate the effective dynamic properties of composites with randomly distributed fibers. Typical examples are presented to show the effects of different pertinent parameters upon the effective wave speed and the attenuation.

Existing studies on slit crack problems have been limited mostly to the electrically impermeable and permeable crack models, which represent the limiting cases of the physical boundary condition. This paper studies the generalized plane problem of a crack in a piezoelectric medium, with the electric boundary condition along the crack surfaces being governed by its opening displacement. The theoretical formulation of this nonlinear problem is based on the use of Fourier transforms and the solution of a system of integral equations, which are solved using Chebyshev polynomials. The analytical solution of the problem clearly shows the transition between permeable and impermeable models with increasing crack opening. Depending on the applied mechanical and electric loads, different modes of crack deformation are predicted and discussed.