Investigation on Stress and Strain Singularity in LEFM


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Stress and strain singularity at crack-tip is the characteristic of Linear Elastic Fracture Mechanics (LEFM). However, the stress, strain and strain energy at crack-tip may be infinite promoting conflicts with linear elastic hypothesis. It is indicated that the geometrical nonlinear near the crack-tip should not be neglected for linear elastic materials. In fact, the crack-tip blunts under high stress and strain, and the singularity vanishes due to the deformation of crack surface when loading. The stress at crack-tip may still be very high even though the singularity vanishes. The low bound of maximum crack-tip stress is the modulus of elastic in plane stress state, while in plain strain state, it is greater than the modulus of elastic, and will increase with the Poisson’s ratio.



Key Engineering Materials (Volumes 306-308)

Edited by:

Ichsan Setya Putra and Djoko Suharto




Z. Yang et al., "Investigation on Stress and Strain Singularity in LEFM", Key Engineering Materials, Vols. 306-308, pp. 31-36, 2006

Online since:

March 2006





[1] Tianyou Fan: The theory foundation of Fracture. The Science Press, Beijing, (2003).

[2] C. Y. Hui, A. Ruina: International Journal of Fracture. Vol. 72 (1995), p.97.

[3] H. C. Hu: Mechanics and Practice. Vol. 9 (1987), p.20.

[4] N. I. Muskhelishvili: Some Basic Problems of the Mathematical Theory of Elasticity. 3nd ed., P. Noordhoff, Groningen, Holland, (1953).

[5] R. J. Sanford: Principles of Fracture Mechanics. Pearson Education, Inc., London, 2003 0. 20 0. 25 0. 30 0. 35 0. 40 0. 45 0. 50 0. 9 1. 0 1. 1 1. 2 1. 3 1. 4 Poisson ratioν σtip /E Plain stress Plane strain Fig. 4 Relation between lower limits of crack-tip maximum stress and Poisson ratio.