摘要
利用波函数展开法给出了含多个沉积层凹陷地形对平面SH波散射二维问题的一个解析解,并以一具有3个沉积层的凹陷地形为例,分析了凹陷地形中沉积层排列次序对SH波散射的影响。结果表明,凹陷地形中沉积层排列次序将显著改变凹陷地形的卓越频率,沉积层的某个(些)排列次序有可能对入射波产生巨大的放大作用;此外,沉积层的刚度、厚度以及凹陷地形的深宽比等均对凹陷地形的放大效应也有一定的影响。
By wave function expansion method,an analytical solution for two-dimensional scattering of plane SH waves around a canyon with multi-layered alluvia was given;and effect of the sequence of the alluvial layers on the scattering of SH waves was studied by an example of a canyon with three alluvial layers.It was demonstrated that,the sequence of alluvial layers in a canyon changes predominant frequencies of the canyon significantly;and large amplification to the incident wave may be caused for certain sequence of the alluvial layers;stiffness and thickness of the alluvial layers,and depth-to-width ratio of the canyon,etc.have influences on the amplification.
引文
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