樁型地震超材料面對近斷層之實驗與可行性研究

Abstract

如何減少地震所帶來的災害和損失，一直是位於環太平洋火山地震帶的台灣所要面對的重要課題，隨著時代的演進抗震技術也日趨成熟。近幾年地震超材料(Seismic Metamaterials)作為新型的減震技術逐漸受到學術與工程界的重視，透過特殊的設計與排列方式，可以形成特定頻率波傳無法通過之屏障，進而使人們能在不改變既有建築物的狀況下建立防止地震波傳入之保護區。然而過往地震超材料相關研究主要面對的都是點波源抑或是固定頻率之波傳，難以貼近真實地震波之特性，故本研究旨在透過實驗室地震之製造地震方法，將其作為地震超材料所要面對之波傳，並且觀察超材料在面對地震波之表現。 本篇研究首先透過數值模擬的方式設計超材料單元，使其尺寸和頻率帶隙(Band Gap)適合實驗室地震設備尺寸及其地震波頻率，後續進行排數分析證實其面對帶隙頻率內之波傳確實能產生折減。完成設計後再透過數值模擬重現文獻中實驗室地震實驗，再將本研究所設計之樁型地震超材料至於其中觀察其對波傳行為的影響。最後再透過3D列印技術製作出矽膠樁型地震超材料試體，首先進行落球實驗證實其對非固定頻率之波傳也能在帶隙範圍內產生折減，後續進行與文獻相似之斷層面實驗並且透過不一樣的配置皆證明樁型地震超材料在面對近斷層之地震波也能降低帶隙範圍內之波傳。 綜合以上模擬與實驗結果，樁型地震超材料在面對真實地震波具有減震之潛力，未來若能進行更多相關模擬以及大規模實驗證明地震超材料之可行性，即可進一步提升地震工程技術，減輕地震所帶來的損害。

Reducing the damage and losses caused by earthquakes has long been a critical challenge for Taiwan, located in the seismically active Pacific Ring of Fire. With the advancement of time, seismic-resistant technologies have gradually matured. In recent years, seismic metamaterials have emerged as a novel passive vibration control technology, gaining increasing attention from both academia and engineering practice. Through specific designs and periodic arrangements, these materials can form frequency-dependent wave-blocking zones, preventing seismic waves from propagating through certain frequency ranges. This enables the creation of protected zones without modifying existing structures. However, most previous studies have focused on point sources or fixed-frequency waves, which do not accurately represent the characteristics of real earthquake ground motions. Therefore, this study employs a laboratory earthquake system to replicate near-real earthquake conditions and examines the performance of seismic metamaterials under such wave propagation scenarios. The study first utilizes numerical simulations to design metamaterial units with dimensions and band gap frequencies compatible with the laboratory seismic system. The row test is then conducted to evaluate the wave attenuation performance for different numbers of metamaterial rows, confirming their effectiveness within the target band gap range. Subsequently, the designed pile-type seismic metamaterial is integrated into a finite element model replicating a previously published laboratory fault simulation to observe its influence on seismic wave propagation. In the experimental stage, silicone-based pile-type metamaterials are fabricated using 3D printing technology. The ball drop experiments confirm their ability to attenuate non-monochromatic waves within the band gap. Further near-fault laboratory earthquake experiments using various configurations also demonstrate that the metamaterials can effectively reduce wave transmission in the specified frequency range. In conclusion, both simulation and experimental results indicate that pile-type seismic metamaterials possess the potential to mitigate seismic waves under realistic conditions. Future research involving larger-scale models and field simulations may further verify their feasibility and contribute to the development of advanced seismic protection strategies.