Two-dimensional microtwist modeling of topological polarization in hinged Kagome lattices and its experimental validation
Two-dimensional microtwist modeling of topological polarization in hinged Kagome lattices and its experimental validation
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DOI：
10.1016/j.ijsolstr.2022.111891
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发表时间：
2022-07
影响因子：
3.6
通讯作者：
Hui Chen;Shaoyun Wang;Xiaopeng Li;Guoliang Huang
中科院分区：
文献类型：
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作者：
Hui Chen;Shaoyun Wang;Xiaopeng Li;Guoliang Huang
Kagome晶格由于其独特的力学性质引起了人们的极大关注，这些性质包括拓扑极化和在某些边缘处的局域零模，这些都对标准的有效连续介质理论提出了挑战。以前的研究主要集中在理想的Kagome晶格与弹簧质量模型。在这项研究中，我们延伸这一范式，探索铰链Kagome晶格走向实际应用，以了解拓扑极化的框架下的microtwist连续。铰链由能够支持拉伸、剪切和弯曲变形的韧带来建模。微扭转弹性，然后制定由于领导阶两尺度渐近和它的本构方程和平衡方程的推导。理论的性能得到了色散关系和周期零模的精确解的验证。我们进一步证明了这个理论的有效性，通过数值模拟以及实验测试。最后，探讨了复杂载荷下的非均匀变形和微扭转介质中的宇称非对称表面波。我们的研究为利用微扭转介质设计、控制和编程铰链基超材料提供了巨大的潜力。
Kagome lattices have recently attracted a great attention because of the unique mechanical properties including their topological polarization and localized zero modes at certain edges, which challenge the standard effective continuum theories. The previous study of these systems has been predominantly focused on the ideal Kagome lattice with the spring–mass models. In this study, we stretch this paradigm by exploring the hinged Kagome lattices towards practical application to understand the topological polarization under the framework of the microtwist continuum. The hinges are modeled by ligaments capable of supporting stretching, shear and bending deformations. The microtwist elasticity is then formulated thanks to leading order two-scale asymptotics and its constitutive and balance equations are derived. Performance of the proposed theory is validated by the exact solution for predicting dispersion relations and periodic zero modes. We further demonstrate the effectiveness of this theory through numerical simulations as well as experimental testing. Finally, nonuniform deformation under complex loadings and parity asymmetric surface waves in microtwist media are explored. Our study provides a great potential of using the microtwist medium to design, control and program hinge-based metamaterials.