Finite Element Fracture Prediction For Wood With Knots and Cross Grain

Authors

  • J. G. Zandbergs
  • F. W. Smith

Keywords:

Finite elements, fracture prediction, wood with defects

Abstract

A finite element/fracture mechanics model has been developed to predict the tension behavior of structural wood members containing defects. The computer code Starwx presented here is used in a preliminary investigation of the effect of global cross grain on the strength of structural wood members with knots. The results indicate a more severe stress condition for the member with global cross grain as compared to the straight grain member.

A method of strength prediction is presented that, unlike other methods, simulates the progressive fracture/failure process in wood, which leads to the ultimate load-carrying capacity of the member. Program Starwx is employed to predict the failure of a wood member containing a knot and global cross grain in a case for which actual test data are available. The member ultimate strength predicted was within 15% of the strength determined by the test.

References

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Published

2007-06-22

Issue

Number 1 / January 1988

Section

Research Contributions

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