Oblique surface cracking and crack closure in an orthotropic medium under contact loading

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2018
Toktaş, Selim Ercihan
In this study, inclined surface cracks in an elastic orthotropic half-plane exposed to contact loading at the material surface are examined for both open and closed crack assumptions. At first, mixed mode stress intensity factors are computed for fully open crack assumption depending on the solution of singular integral equations, obtained by Full Fourier Transform techniques. Unless fully open crack assumption is valid, the suitable crack closure mode is determined. Both crack tip and full length closure modes are examined. Singular integral equations are solved with a suitable expansion-collocation technique depending on the closure mode. Finally, the closed portions of the cracks, contact pressure distributions between crack faces and modified mode II stress intensity factors are computed considering sliding crack face conditions. The main result of the analyses is the influence of the material parameters, the crack orientation angle and applied load on mixed mode stress intensity factors, closed portions of the cracks and the contact pressure distributions in the closed parts.

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Citation Formats
S. E. Toktaş, “Oblique surface cracking and crack closure in an orthotropic medium under contact loading,” M.S. - Master of Science, Middle East Technical University, 2018.