Abstract
This paper proposes a novel family of intelligent piezoelectric composite structures for the purpose of establishing structural self-awareness via integrating the function of load bearing with the capability of transmitting and receiving high frequency mechanical waves. To develop a deep insight into the mechanism of the intelligent structure, coupled-field Finite Element Models (FEM) are constructed to conduct the transient dynamic analysis for understanding the wave propagation characteristics in piezoelectric composite beams. In particular, the model employs the Equivalent Average Parameter (EAP) method, utilizing overall and nominal quantities, in order to simulate the self-sensing composites. The guided wave generation and tuning characteristics are investigated utilizing the harmonic analysis model with absorbing boundary conditions. Furthermore, meticulously crafted through a continuous process of material ratio optimization and process step refinement, sample piezoelectric composite plates are fabricated to ensure the highest degree of sensitivity and reliability during experimental demonstration. A pitch-catch active sensing setup is utilized to verify the capability of the piezoelectric composites for generating and receiving ultrasonic guided wave. Moreover, a Scanning Laser Doppler Vibrometer (SLDV) is applied to visualize the waves generated in the structure for analyzing the propagation modes of ultrasonic guided waves in the piezoelectric composite material. The numerical simulations and experimental demonstrations showcase that the proposed piezoelectric composite system possesses great potential for realizing self-awareness for future intelligent structures. The paper finished with summary, concluding remarks, and suggestions for future work.
