SH波入射半空间双相介质界面附近圆形衬砌的动力分析

利用复变函数和Green函数法研究了无限半空间中双相介质界面附近圆形衬砌对SH波的散射与动应力集中问题。该问题的解答采用镜像法，首先构造出含有圆形衬砌的直角平面区域出平面问题的Green函数，然后利用“契合”技术，并根据界面处位移连续性条件将解答归结为具有弱奇异性的第一类Fredholm积分方程组的求解，结合散射波的衰减特性，直接离散该方程组，把积分方程组转化为线性代数方程组可得到该问题的数值结果。最后，通过算例分析了不同介质参数、几何参数和入射波时圆形衬砌界面的动应力集中情况。

DYNAMIC ANALYSIS OF THE SCATTERING OF SH-WAVE BY CIRCULAR LINING NEAR BIMATERIAL INTERFACE IN HALF-SPACE

The scattering of SH-wave by circular lining near bimaterial interface in half-space and dynamic stress concentration are studied, based on the complex function method and Green’s function method. The solution of present problem is given by “image” method. Firstly, a suitable Green’s function is constructed, which is the essential solution of displacement field for an elastic right-angle plane with a circular lining impacted by anti-plane harmonic line source loading at horizontal surface. Secondly, the method of “conjunction” is used to construct the scattering model of SH-wave, then a series of Fredholm integral equations of first kind for determining the unknown forces can be set up through continuity conditions that are expressed in terms of the Green's function. Finally, the numerical examples showed that the concentration of dynamic stress depended on the incident frequency and angle of SH-wave, the geometrical position of circular cavity, and the different media combination parameters.