二维地表相邻多个半圆弧沟谷对SH波的散射

本文由解析法研究了二维地表相信多个圆弧沟谷对稳态ＳＨ波的散射问题。文中把相邻多个圆弧沟谷对波的多重散射表达为各局部坐标的Ｆｏｕｒｉｅｒ－Ｂｅｓｓｅｌ级数之和，再利用Ｇｒａｆ加法公式在某一局部坐标中表达为双重级数形式，将问题归结为对一组线性方程的求解。最后，作为例子，给出了相信两圆弧沟谷对波散射的数值结果，讨论了沟谷对波的屏蔽、隔振作用及沟谷之间的相互作用。

SCATTERING OF PLANE SH-WAVES BY MULTIPLE CIRCULAR-ARC VALLEYS AT THE TWO-DIMENSIONAL SURFACE OF THE EARTH

This paper deals with the scattering of plane harmonic SH-Waves by multiple circular-arc valleys at the two-dimensional surface of the earth using analytic method. The multiple scattering displacement is first expressed as the sum of Fourier-Bessel series of each local coordinate and is then transformed into a dual series of a local coordinate by Graf's addition formula. The problem of multiple scattering of SH-Waves is reduced to solving an infinite algebraic equation system. As an example the numerical results of scattering by two circular-arc valleys are finally presented to discuss the effects of screening,vibration isolation and interaction between valleys.