摘要
该文基于周期结构带隙设计思想,针对在中远场情况下具有较强破坏性的Rayleigh表面波,尤其是20 Hz以下的低频波,设计了新型周期格栅式表面波屏障,并对其频散曲线和频率响应进行了数值模拟。探讨了波屏障结构参数对带隙的影响。研究结果表明:周期格栅式表面波屏障具有良好的隔震性能。
Based on the elastic wave band-gap theory for periodic structures, a novel grid barrier in periodic arrangement was designed for Rayleigh surface waves, especially for those with frequencies below 20 Hz.Rayleigh surface waves may result in severe destruction in middle and far fields. Numerical simulation on the dispersion curves and frequency responses was carried out, and the influences of the geometrical parameters on the band gaps were discussed. The results show that the surface wave barrier exhibits good seismic isolation performance.
引文
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