地表下圆形夹塞区出平面散射对地面运动的影响

采用波函数展开方法，提出弹性半空间埋藏的圆形弹性夹塞区对平面ＳＨ波二维散射的封闭级数解答．利用内域型Ｇｒａｆ加法公式，将解答归结为一组无穷代数方程组的求解．通过对无穷方程组的截断计算，得到了解答的数值结果；并通过边值条件的收敛，检验了截断计算的精度．最后给出若干典型算例说明夹塞区产生的散射场对地表运动的复杂影响．

EFFECT OF A CIRCULAR UNDERGROUND INCLUSION ON SURFACE MOTION UNDER INCIDENT PLANE SH WAVES

A closed-form solution of two-dimensional scattering of plane SH waves by acircular underground inclusion in a half-space is presented using the wave functions expansion. The solution is reduced to solving a set of infinite linear algebraic equations using the interior region form of Graf's addition theorem. Numerical solutions are obtained by truncation of the infinite equations and their accuracies are demonstrated by convergence of the numerical results to the exact boundary condition with the increasing of the truncation order. Complicated effects of the depth-to-width ratio of the inclusion on surface ground motion are finally illustrated.