十字分形地震超材料隔震性能  

Seismic Isolation Performance of Cross-fractal Seismic Metamaterials

作　　者：石南南 亢志宽 罗方慧 刘晗 王利辉 赵卓 SHI Nannan;KANG Zhikuan;LUO Fanghui;LIU Han;WANG Lihui;ZHAO Zhuo(Beijing Key Laboratory of Earthquake Engineering and Structural Retrofit,Beijing University of Technology,Beijing 100124,China)

机构地区：[1]北京工业大学工程抗震与结构诊治北京市重点实验室,北京100124

出　　处：《北京工业大学学报》2023年第1期33-43,共11页Journal of Beijing University of Technology

基　　金：国家自然科学基金资助项目(51708008)。

摘　　要：为了解决基于表面波理论的地震超材料带隙窄的问题,设计了一种基于十字分形柱的低频宽带隙地震超材料,并通过数值模拟计算其频散曲线,发现三阶十字分形地震超材料的相对带宽高达60%.对不同阶数十字分形地震超材料的频散曲线进行比较研究,以阐明分形地震超材料带隙扩展的机理.通过材料参数分析,研究不同材料参数对带隙宽度及位置的影响.为验证所设计的地震超材料对实际地震波的屏蔽效果,进行频域和时域分析.通过对El Centro地震波和Taft地震波的瞬态动力学分析发现,三阶十字分形地震超材料可以将2种地震表面波位于带隙频率范围内的加速度幅值降低50%以上,具有良好的隔震性能.To solve the problem of the narrow band gap of seismic metamaterials based on surface wave theory,a low-frequency and wide-bandgap seismic metamaterial based on cross fractal columns was designed in this paper,and the dispersion curve of the designed structure was calculated by numerical simulation.It is found that the relative band gap width of the third-order cross-fractal seismic metamaterial is as high as 60%.The dispersion curve of cross-fractal metamaterials of different orders was comparatively studied to clarify the mechanism of the band gap expansion of fractal seismic metamaterials.Through material parameter analysis,the influence of different material parameters on the width and position of the band gap was studied.To verify the shielding effect of the designed seismic metamaterial against actual seismic waves,time-domain and frequency-domain analyses were carried out.Through the transient dynamic analysis of El Centro seismic wave and Taft seismic wave,it is found that the third-order cross-fractal seismic metamaterial can reduce the acceleration amplitude of the two seismic surface waves in the band gap frequency range by more than 50%,which indicates that it has good isolation seismic performance.

关 键 词：地震超材料 十字分形结构 地震表面波 带隙 隔震 透射谱 

分 类 号：TU352[建筑科学—结构工程]