Many important applications of crack mechanics involve self-equilibrating residual or thermal stress fields. For these types of problems, the traditional fracture mechanics approach based on the superposition principle has ignored the effect of crack surface contact when the crack-tip propagates into the residual compressive region. Contact between the crack faces and the wedging action are responsible for subsequent crack-tip reopening, which often leads to a much larger mode I stress intensity factor. In this study, an analytical approach is used to study the effect of crack face contact for a period array of collinear cracks embedded in several typical residual stress fields. It is found that the nonlinear contact between crack surfaces dominates the cracking behavior in residual/thermal stress fields, which is responsible for crack coalescence.
Bibliographical noteThis work was supported in part by the Multi-University Research Initiative on the Science Underpinning Prime Reliant Coatings, which is funded at Columbia University by Grant No. 04-123219, and in part by the Department of Civil Engineering and Engineering Mechanics, Columbia University.
- Collinear cracks
- Contact mechanics
- Crack mechanics
- Stress intensity factor