Crack Paths 2012

the cracked pipe. It was found that the crack shape is influenced by the presence of

residual stresses and a significant increase of the stress intensity factor in comparison

with a pipe without residual stresses was observed. An approximative equation for the

stress intensity factor estimation in the pipe with residual stresses was presented and

good agreement with the numerically obtained data was found.

The results presented can be helpful for a rapid lifetime estimation of polyolefin

pipelines.

A C K N O W L E D G E M E N T

This work was supported by grant P108/12/1560 of the Czech Science Foundation and

by the Specific academic research grant of the Ministry of Education, Youth and Sports

of the Czech Republic provided to Brno University of Technology, Faculty of

Mechanical Engineering No. FSI-J-12-21/1693.

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