Publication detail

Numerical simulations of cracked round bar test: Effect of residual stresses and crack asymmetry

PODUŠKA, J. HUTAŘ, P. FRANK, A. KUČERA, J. SADÍLEK, J. PINTER, G. NÁHLÍK, L.

Original Title

Numerical simulations of cracked round bar test: Effect of residual stresses and crack asymmetry

Type

journal article in Web of Science

Language

English

Original Abstract

The Cracked Round Bar (abbreviated as CRB in the following) test is used as standardized accelerated testing method for simple ranking of polyethylene pipes based on measuring number of cycles to failure of the cyclically loaded CRB specimen. It can also be used for the slow crack growth rate evaluation of the tested material. This paper deals with the issue of asymmetrically growing cracks in CRB specimens and possible influence of the asymmetry on the results of CRB tests, both the number of cycles to failure and the crack growth rates. It is assumed that the asymmetry is caused by presence of residual stress in the CRB specimens. In the first part of the paper, residual stress in two polyethylene pipes (produced using different extrusion speed) is investigated. Then CRB specimens made from these pipes are also examined regarding the residual stress and the results are compared. The found residual stress distributions are used as input for the following finite element method (FEM) simulation of crack growth in the CRB specimens. The FEM model results are then evaluated and fatigue crack growth rates for asymmetrically growing cracks are calculated. They are compared to the results for symmetrically growing cracks and influence on the results and its significance is discussed. In the end, CRB specimen lifetime prediction is carried out and the influence of the asymmetry on the obtained number of cycles to the failure is also addressed.

Keywords

Asymmetrical crack;Cracked round bar test;Fatigue crack growth rate;Polyethylene pipe;Residual stress

Authors

PODUŠKA, J.; HUTAŘ, P.; FRANK, A.; KUČERA, J.; SADÍLEK, J.; PINTER, G.; NÁHLÍK, L.

Released

13. 11. 2018

Publisher

Elsevier Ltd

ISBN

0013-7944

Periodical

Engineering Fracture Mechanics

Year of study

203

Number

2018

State

United Kingdom of Great Britain and Northern Ireland

Pages from

18

Pages to

31

Pages count

14

URL

https://www.sciencedirect.com/science/article/pii/S0013794418300997?via%3Dihub

BibTex

@article{BUT151149,
  author="Jan {Poduška} and Pavel {Hutař} and Andreas {Frank} and Jaroslav {Kučera} and Jiří {Sadílek} and Gerald {Pinter} and Luboš {Náhlík}",
  title="Numerical simulations of cracked round bar test: Effect of residual stresses and crack asymmetry",
  journal="Engineering Fracture Mechanics",
  year="2018",
  volume="203",
  number="2018",
  pages="18--31",
  doi="10.1016/j.engfracmech.2018.06.032",
  issn="0013-7944",
  url="https://www.sciencedirect.com/science/article/pii/S0013794418300997?via%3Dihub"
}