本文旨在探討異向性材料動態裂紋第Ｉ型擴展時，裂紋線及裂紋面之位移和應力兩者與擴展速度的關係，研究結果顯示，裂紋擴展速度對裂紋線及裂紋面之位移和應力是完全透過實數矩陣S(v)、L(v) 來影響的，由於此二實矩陣可以用彈性常數直接表出其顯式，且此二矩陣在退化材料亦適用，故本研究成果在動態裂紋擴展下，對裂紋線及裂紋面之位移和應力之了解應有助益。

The aim of this paper is to analyze the effect of the speed of the dynamic propagating crack on the fields lying on the crack line and crack faces. It is found that this effect is completely through matrices S(v)and L(v).Since both matrices are able to be expressed explicitly in terms of the elastic stiffness for general anisotropic material, the effect of the propagating speed and material constants on the crack line and crack faces may be observed explicitly. Moreover, present results are valid even for degenerate materials.

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