Abstract
In this paper, flexural wave in a steel-concrete composite beam with periodically surface-bonded cement-based piezoelectric patches (CPP) is studied. The composite beam is designed using the idea of the phononic crystals. The external capacitor shunt circuit is connected to the CPP for regulating the band gap of the composite beam. The flexural wave equations are established by Euler beam theory. Using plane wave expansion method and transfer matrix method, the complex band structures of the flexural wave are calculated to investigate the frequency range and the vibration reduction in band gap. From the numerical results, it is shown that by tuning the external capacitor shunt circuit, the band gap of the periodic structure can be regulated conveniently. The regulation capability of the negative capacitance shunt circuit is stronger than that of the positive capacitance. We can obtain different starting low-frequency and wide band gaps by using negative capacitance. The proposed approach gives a promising way to design intelligent beams whose band gaps can be tuned without modifying the structures.