近年來，不少學者投入地震超材料的領域，開始探索及研究如何有效衰減地震表面波，而本文則探討表面波中具水平向振動、且僅在由較硬之半無限域與較軟之導引層所組成的層狀介質中傳遞的洛夫波。首先，有別於以往較簡化之等向性波傳介質假設，本文以橫斷面等向性材料來模擬廣大地球表面中的沉積岩，證實橫向與縱向之剪力模數能有效控制洛夫波於導引層與半無限域之波傳行為。此外，本文亦研究了由地層錯動造成之初始應力對洛夫波之波傳影響。本文從複合材料力學中的平均值理論出發，在導引層表面加入由水平向共振器組成之地震超材料，於洛夫波之頻散關係中成功產生帶隙，再來引入簡廷宇等人(2019)設計之地震超材料單元結構，發現較大之橫向剪力模數能造成較高的帶隙上邊界頻率、進而導致更為寬廣的頻帶，最後，以有限元素軟體進行三維全域模擬，其結果顯示當地震超材料之深度與導引層厚度相當時，能夠大幅減少帶隙內表面區域之位移反應。

We investigate the propagation of shear polarized surface wave, in the form of Love waves, with mechanical resonators on the top of semi-infinite layered media. Both the top soft guiding layer and the semi-infinite substrate, are taken to be transversely isotropic, in a simulation of a type of surface wave in the seismic ground motion of the Earth. In addition, the effect of initial stresses in the soft layer is also examined. The objective of this work is to explore the possibility to control the Love waves dispersive behavior by varying the properties of transversely isotropic phases and the resonators mechanical parameters. We also perform 3D finite element simulations to demonstrate the performance of effects. The results suggest that transverse isotropy has little influences on the width of bandgaps, but is sufficient to control the propagation behavior of Love waves with specific values of shear moduli. It is also observed that when the depth of seismic metamaterials is extended to the half-space from the top surface, that is, the height of resonators nearly equals to the thickness of the upper soft guiding layer, the magnitude of displacement fields on the surface in the protected area can be significantly attenuated.

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