Vibration control and optimization of topological metamaterial plates

This study presents the design of a locally resonant topological metamaterial plate for enhanced vibration control. By altering the height difference ([Formula: see text]) of the oscillators in the initial unit cell, spatial inversion symmetry breaking and band inversion are achieved. Supercells composed of topological crystals with different topological phases were used to reveal the presence of elastic wave bandgaps and two types of edge states with different valley vortex directions in the band structure. Based on this, we constructed several metamaterial plates to verify the wave-guiding capabilities of the topological edge states, demonstrating their robust propagation characteristics such as backscattering suppression and defect immunity, and designed specific waveguiding paths that effectively isolate and protect a target area from vibrational energy. Furthermore, the influence of key parameters on the bandgap in the band structure of locally resonant topological metamaterials was discussed in detail. The bandgap frequencies were optimized using a multiobjective particle swarm optimization algorithm based on single-objective and nondominated sorting. This provides a feasible solution for elastic wave manipulation using topological states in plates for civil engineering applications.