Smart piezoelectric module-based wave energy measurement for crack damage evaluation of concrete beams

Concrete structures under the action of service load and other adversary factors are inevitable of reduced safety, durability and bearing capacity due to crack damage. In this paper, based on piezoelectric wave propagation method, smart piezoelectric modules (SPMs) made of piezoelectric ceramics are embedded in concrete to evaluate crack damage. A calibration device is first designed to examine the basic performance of SPMs, and a correlation method of SPMs with respect to crack damage is established. By processing the wave signals with various degrees of crack damage, the wave energy value capable of evaluating the crack damage and predicting its growth in concrete beams is identified as the sensitive parameter. The numerical finite element simulation is also conducted to validate and demonstrate the trend of crack-induced wave attenuation as observed in the experimental testing. Finally, the size effect of concrete beams and the location of embedded SPMs on the sensitivity of crack damage evaluation are studied, and the recommendations on effective crack damage evaluation and placement of embedded SPMs are provided. The crack identification method using the SPMs and wave propagation energy developed in this study can be potentially adopted in practices for crack damage evaluation in concrete structures and development of smart infrastructure.