A novel architected lattice metamaterial with broadband and multiband bandgap characteristics is studied here. A slight structural modification in a regular lattice structure has succeeded to significantly magnify the vibration attenuation capability of these lightweight periodic lattices. The vibration control properties of these lattices are investigated both theoretically and experimentally. The sinusoidal-shaped ligament is found useful in generating a broadband Bragg bandgap with robust wave attenuation characteristics. The embedment of circular masses at the center of these lattices help induce multiband low frequency bandgaps. The properties of sinusoidal-shaped ligament such as the number of sine wave undulations/ligament wavelength and the effect of central mass radius on bandgaps are investigated. Introducing material damping flattens the transmission peaks and it results in a broadband bandgap distributed throughout the frequency spectrum. The experimental results are in good agreement with numerical solutions. The proposed lightweight lattice metamaterial can be effectively applied at any length scale for controlling acoustic/elastic waves propagation.

本文研究了具有宽带和多带隙特性的新型结构化格构超材料。规则晶格结构中的轻微结构修改已成功显着放大了这些轻型周期性晶格的振动衰减能力。理论和实验研究了这些晶格的振动控制特性。发现正弦形韧带可用于产生具有鲁棒的波衰减特性的宽带布拉格带隙。在这些晶格的中心嵌入圆形质量有助于诱导多频带低频带隙。研究了正弦形韧带的特性，例如正弦波起伏数/韧带波长以及中心质量半径对带隙的影响。引入材料阻尼会使传输峰值变平，并且会导致在整个频谱上分布的宽带带隙。实验结果与数值解吻合良好。所提出的轻质晶格超材料可以有效地应用于任何长度尺度，以控制声/弹性波的传播。