后屈曲张拉整体超材料的建模和优化设计OA北大核心

Achieving a balance between low-frequency bandgaps and high load capacity is a critical challenge in metamaterial design.Leveraging the post-buckling behavior of bars,this study proposes a novel tensegrity metamaterial where post-buckling induces a reduction in structural stiffness,thereby enabling low-frequency vibration isolation while enhancing load-bearing capacity.The elliptic integral method is employed to rapidly compute post-buckling deformations and determine the stiffness of the tensegrity unit.Bandgap frequencies are calculated using Bloch's theorem under periodic boundary conditions,combined with a spring-mass diatomic chain model.To optimize both band gap and load capacity,a data-driven,dual-objective optimization method is employed,yielding the Pareto frontier for the metamaterial's ultimate load and lower bandgap limit.The results demonstrate that the optimized structure can achieve bandgap frequency as low as 3 Hz,with a load capacity exceeding 100 N.Compared to existing low-frequency vibration isolation metamaterials,the ultimate load capacity is increased by over 3.6 times at the same bandgap frequency.