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Abstract

The transient elastodynamic response due to concentrated normal impact load on the faces of a semi-infinite crack in an orthotropic material is examined. In contrast to earlier papers where numerical approximations were used, a closed form solution for the stress intensity factor history around the crack tip is found here. Laplace and Fourier transforms together with the Wiener-Hopf technique are employed to solve the equations of motion in terms of displacements. Even though the problem has characteristic length, it has been shown in previous works that the Wiener-Hopf technique can be applied. The asymptotic expression for the stress near the crack tip is analyzed which leads to the dynamic stress intensity factor in mode I. Similarly to the isotropic case, it is found that the stress intensity factor has a singularity and discontinuity when the Rayleigh wave emitted from the load arrives at the crack tip. Results are presented for orthotropic materials as well as for the isotropic materials. The closed form solution is given by simple integral and algebraic expressions and does not exhibit the spurious oscillations seen in earlier numerical solutions.

Keywords

stress intensity factor dynamic fracture orthotropic materials

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References

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Dynamic Stress Intensity Factor due to Concentrated Normal Loads on Semi-Infinite Cracks in Orthotropic Materials

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