Session: 18: Student poster competition

Paper Number: 118530

118530 - Self-Sensing Piezoelectric Composite Structures With Disperse Active Neurons 

Structural health monitoring (SHM) endeavors to establish contemporaneous and proactive procedures for assessing structural integrity and evaluating the potential dangers of structural damage. The exigency for SHM has amplified significantly in recent times with the escalating demand for secure and more productive infrastructures. The invention of intelligent structures equipped with self-sensing capabilities holds the potential to curtail maintenance expenses and forestall calamitous mishaps. Various types of sensors can be implemented on the host structures for realizing such a purpose. However, the installation of sensors is an indispensable requirement for achieving the goal of SHM for conventional structures. Surface-mounted sensors commonly necessitate meticulous preservation and are susceptible to external abrasions. Conversely, embedded sensors may negatively impact material robustness and fatigue effectiveness by functioning as a source of stress concentration. Consequently, an innovative structure-sensor amalgamation system is sought-after to establish a pioneering framework for self-sensing intelligent structures.

This paper proposes a novel family of intelligent piezoelectric composite structures for the purpose of establishing structural self-awareness by integrating the capability of Electromechanical Impedance Spectroscopy (EMIS) methodology and transmitting and receiving high frequency mechanical waves. To develop a deeper understanding of the mechanism underlying the intelligent structure, coupled-field finite element models are constructed to conduct modal analysis. The proposed model is inspired by the Equivalent Average Parameter (EAP) method employing a whole plate to demonstrate the finite element model. Guided wave generation and reception are modeled to showcase the self-sensing capability of the proposed composite structure, and a Root Mean Square Deviation (RMSD) damage metric is subsequently applied to determine the position of the structural damage by EMIS. A detailed account of the manufacturing process of the piezoelectric composite structures is provided, which involves material ratio optimization and process step refinement, starting from the selection of raw materials to the final production of the piezoelectric composite structure. The process parameters such as temperature, pressure, and curing time are controlled to ensure the highest degree of sensitivity and reliability during experimental demonstration, and the experimental results' reliability is increased. The capability of the piezoelectric composites for generating and receiving ultrasonic guided wave signals is verified using a pitch-catch active sensing setup, and the propagation modes of ultrasonic guided waves in the piezoelectric composite material are analyzed using a scanning laser Doppler vibrometer (SLDV) to visualize the waves generated in the structure. Finally, electromechanical impedance method is employed and implemented to form an interrogation scheme for the occurrence of damage and evaluation. It is demonstrated through numerical simulations and experimental demonstrations that the proposed piezoelectric composite system possesses significant potential for realizing self-awareness in future intelligent structures.

Presenting Author: Shulong Zhou Shanghai Jiao Tong University

Presenting Author Biography: He is a Ph.d student