# 이방성비가 큰 직교이방성체의 반 무한 균열에 대한 동적 응력확대계수에 관한 연구

• Published : 2000.06.01
• 13 2

#### Abstract

When the half infinite crack in the orthotropic material strip with a large anisotropic ratio(E11>>E22) propagates with constant velocity, dynamic stress component $\sigma$y occurre d along the $\chi$ axis is derived by using the Fourier transformation and Wiener-Hopf technique, and the dynamic stress intensity factor is derived. The dynamic stress intensity factor depends on a crack velocity, mechanical properties and specimen hight. The normalized dynamic stress intensity factors approach the maximum values when normalized time(=Cs/a) is about 2. They have the constant values when the normalized time is greater than or equal to about 2, and decrease with increasing a/h(h: specimen hight, a: crack length) and the normalized crack propagation velocity( = c/Cs, Cs: shear wave velocity, c: crack propagation velocity).

#### Keywords

Orthotropic Material;Strip;Shear Wave Velocity;Fourier Transformation;Wiener-Hopf Technique;Dynamic Stress Intensity Factor;Normal Impact Load;Crack Surface;Anisotropic Ratio;Half Infinite Crack

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