International Journal of Fracture

, Volume 167, Issue 2, pp 195–209 | Cite as

A proposed mixed-mode fracture specimen for wood under creep loadings

  • Rostand Moutou Pitti
  • Frédéric Dubois
  • Octavian Pop
Original Paper


A mixed-mode fracture specimen was designed in this paper. This geometry is a judicious compromise between a modified Double Cantilever Beam specimen and Compact Tension Shear specimens. The main objective is to propose a specimen which traduces a stable crack growth during creep loading taking into account viscoelastic behaviour under mixed-mode loadings. The numerical design is based on the instantaneous response traduced by a crack growth stability zone. This zone is characterized by a decrease of the instantaneous energy release rate versus the crack length. In order to obtain a mixed-mode separation, the paper deals with the use of the M-integral approach implemented in finite element software, according to energetic fracture criterions. In these considerations, a numerical geometric optimization is operated for different mixed-mode ratios. Finally, a common specimen which provides to obtain fracture parameters, viscoelastic properties and creep crack growth process for different mixed-mode configurations is proposed.


Mixed modes fractures Wood specimen M integral Finite element analysis 


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Copyright information

© Springer Science+Business Media B.V. 2010

Authors and Affiliations

  • Rostand Moutou Pitti
    • 1
  • Frédéric Dubois
    • 2
  • Octavian Pop
    • 2
  1. 1.Clermont Université, Université Blaise Pascal, Laboratoire de Mécanique et IngénieriesClermont FerrandFrance
  2. 2.Université de Limoges, GEMH-GCD, Centre Universitaire Génie CivilEgletonsFrance

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