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Averaged strain energy density to assess mixed mode I/III fracture of U-notched GPPS samples

  • Saboori, Behnam (Fatigue and Fracture Research Laboratory, Center of Excellence in Experimental Solid Mechanics and Dynamics, School of Mechanical Engineering, Iran University of Science and Technology) ;
  • Torabi, A.R. (Fracture Research Laboratory, Faculty of New Sciences and Technologies, University of Tehran) ;
  • Berto, F. (Department of Mechanical and Industrial Engineering, Norwegian University of Science and Technology (NTNU)) ;
  • Razavi, S.M.J. (Department of Mechanical and Industrial Engineering, Norwegian University of Science and Technology (NTNU))
  • Received : 2017.10.03
  • Accepted : 2018.01.10
  • Published : 2018.03.25

Abstract

In the present contribution, fracture resistance of U-notched GPPS members under mixed mode I/III loading conditions is assessed by using the Averaged Strain Energy Density (ASED) criterion. This criterion has been founded based on the ASED parameter averaged over a well-defined control volume embracing the notch edge. The validation of the theoretical criterion predictions is evaluated through comparing with the results of a series of mixed mode I/III fracture tests conducted on rectangular-shaped GPPS specimens weakened by a single edge U-notch. A recently developed apparatus for mixed mode I/III fracture experiments is employed for measuring the fracture loads of the specimens. The test samples are fabricated with different notch tip radii with the aim of evaluating the influence of this major feature of the U-notched components on the mixed mode I/III fracture behavior. It is shown that the onset of brittle fracture in U-notched GPPS specimens under various combinations of tension and out-of-plane shear can well be predicted by means of the ASED criterion.

Keywords

References

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