Comparison of the Mechanical Properties of Branch and Stem Wood for Three Species


  • Lidia Gurau
  • Marina Cionca
  • Hugh Mansfield-Williams
  • Gervais Sawyer
  • Octavia Zeleniuc


Branch wood, stem wood, compression parallel to the grain, bending strength, modulus of elasticity


Branch wood could be used in new added-value products as an alternative to stem wood provided that its characteristics are known and understood. This article compares the modulus of elasticity (MOE), modulus of rupture (MOR), and compression strength of maple (Acer spp.) and Scots pine (Pinus sylvestris L.) and the compression strength of beech (Fagus sylvatica L.) branch wood with stem wood. The mechanical tests showed that the MOE and compression strength of maple branch wood were slightly lower than those of stem wood, maple MOR was slightly higher for branch wood, and beech compression strength was similar for branch and stem wood. However, the MOR and compression strength of Scots pine branch wood were approximately one-half of those of stem wood, whereas the MOE was approximately one-third. Branch wood had a higher density than corresponding stem wood, except for Scots pine. No correlation was observed between branch density and mechanical strength except for MOR.


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Research Contributions