XXI International Congress of Theoretical and Applied Mechanics
Warsaw, Poland, August 15-21, 2004

Experimental and Numerical Crack Growth in a Special Geometry

Liviu Marsavina (1), Dan M. Constantinescu (2)
1. Department of Strength of Materials, University “Politehnica” of Timisoara, Timisoara, Romania
2. Department of Strength of Materials, University “Politehnica” of Bucharest, Bucharest, Romania

From experimental tests on a motor grain model it appears that both SIF values and crack geometry during growth are quite variable due to shear modes for the off-axis inclined cracks. The numerical study was to find the SIFs versus crack length for three different configurations: symmetric crack, off axis straight- in crack and off-axis inclined crack. The experimental off-axis straight-in crack remains straight in growth after some minor rearrangements, and Mode I is present. For the off-axis inclined crack, which turns on a curved path, after some limited amount of growth Mode II as well as Mode I remained. The numerical simulation shows a rapid change of direction and presence of Mode I. At maximum depth all the experimental 3-D SIFs were smaller than the numerical 2-D corresponding values. For complete three-dimensional numerical simulations mode III has to be considered.

Extended Summary (PDF)