Wood Science and Technology

, Volume 31, Issue 1, pp 17–34 | Cite as

Failure analysis of laminated timber beams reinforced with glass fibre composites

  • S. Hallström
  • J. L. Grenestedt
Article
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Summary

A qualitative analysis is presented of failure, perpendicular to the grain, in laminated timber reinforced with a glass fibre composite. The study is focused on beams with holes of different shape. The stress by corners, infinitesimal cracks and finite cracks are investigated. An initial crack model is suggested that brings about some of the phenomena observed in earlier performed experiments. A crack appears to propagate in the wood but is retarded in the reinforced beams. Eventually, the composite will fracture and failure of the beam follows. Finite element computations suggest that the reinforcement decreases the stress intensity at cracks in the wood and acts as a crack stopper. The reinforcing effect increases with the crack length. A point stress criterion is used to predict failure in the fibre composite.

Keywords

Stress Intensity Timber Crack Length Stopper Stress Criterion 
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Copyright information

© Springer-Vertag 1997

Authors and Affiliations

  • S. Hallström
    • 1
  • J. L. Grenestedt
    • 1
  1. 1.Department of Aeronautics, Division of Lightweight StructuresKungliga Tekniska Högskolan (Royal Institute of Technology)StockholmSweden

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