波型の境界面における弾性波の反射,屈折 : 第3報 SV波入射の場合および位相変化

To ascertain and supplement previous results obtained in the case of a P wave incident upon a corrugated interface, the case of incidence of an SV wave and the phase change upon reflection and refraction were considered. In the case of normal incidence of an SV wave, computation for three models and in the case of oblique incidence of an SV wave that for angles of incidence smaller than 16° for one model were made. Although these results support those for the case of an incident P wave, there are several new features. For example, it is not always valid for large angles of incidence that the effect of corrugation is larger on reflection than on refraction, since the amplitude of regularly reflected S waves is affected by the angle of incidence. Phase changes upon reflection and refraction are not large for regular waves. The velocity contrast between media concerned seems to play an important role for phase changes. For irregular waves there are large phase changes, but it is considered that the contribution to the amplitude of waves is not large since irregular waves travel in different directions to each other.波型の境界面へSV波が入射する場合を,前報と同じくRayleighの方法によつて解き,垂直入射の場合にはP波入射の時と同じ3種類のモデルについて,斜め入射の場合には1つのモデルについて入射角16°以下について,計算を行なつて従来の結果と比較してみた.大部分はP波入射の場合の結果と矛盾しないが,入射波が異なるために若干の細かい点について異つた傾向を得た.例えば正常S波について入射角が大きくなり境界面の波長が短かくなると減少の傾向が見られる.また,正常反射S波が入射角によつて振幅がかなり変わるので,大きい入射角については凹凸の効果が屈折波よりも反射波に大きいとは必ずしもいえない