Investigator: Ing. Stanislav Seitl, Ph.D.
Number of Project: 101/04/P001
Agency: Czech Science Foundation
Duration: 01. 01. 2004 - 31. 12. 2006

The proposal aims to apply the approach of the two parameter constrained based fracture mechanics on determination of the fatigue threshold value of stress intensity factor. The different levels of a stress constraint due to the specimen geometry will be quantified by means of the T-stress. The main goal of the project is to elucidate the effect of the parameter T on threshold value of propagation fatigue cracks. The problem will be solved numerically by means of the finite element method and results will be compared with experimental measurements provided mainly on steels of the Czech production (for example steel 12050.1) The results obtained contribute to those achieved during solution of the basic project and makes it possible better estimations of fatigue life time of real structures.

Knésl, Z., Hutař,P., Seitl, S.: Constraint aspects of the evaluation of fatigue test results in Paris region, Communication 2006, Volume 4: pp. 25-28.

Seitl, S., Knésl, Z. Two Parameter Fracture Mechanics: Fatigue Crack Behavior under Mixed Mode Conditions, Engineering Fracture Mechanics, Volume 75, Issues 3-4, 857-865, 2008

Seitl S., Hutař, P.: Fatigue crack propagation near threshold region in framework two-parameter fracture mechanics, Journal Materials and Technology, 2007, 41(3), 135-138

Hutař, P., Seitl, S., Knésl, Z., Effect of constraint on fatigue crack propagation near threshold in medium carbon steel, Computational materials Science, Vol. 37, 51-57, 2006.