Metamaterial possesses a number of attractive features such as frequency filtering, wave guiding, wave focusing,
etc. Conventionally, the realization of metamaterial is through the careful design of unit-cell of a mechanical structure
which typically exhibits spatial periodicity. In this research, we propose the development of adaptive metamaterial
beams with coupled circuits between adjacent piezoelectric transducers to realize multi-targeted bandgaps. To
characterize the wave propagation attenuation, a numerical model based on the transfer matrix method and Bloch theory
is formulated to predict the complex band structure of the infinite periodic structure. It is shown theoretically that
three separate bandgaps can be generated compared to only one in the conventional LC-shunt since three resonating
loops can be formed in the circuit due to the coupling effect. Consequently, wave propagation or vibration can be
suppressed effectively inside those bandgap frequencies when the structure is subjected to vibration sources with
multiple frequency components.
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