Heart Shakes and Growth Stresses
AbstractHeart shakes are often observed to accompany crosscutting of tree trunks and have been thought to be due to release of longitudinal strain energy in the trunk during cutting. Using a simple model of stresses in the trunk, the authors have attempted to link shake development quantitatively with release of axial strain. On the basis of the analysis, however, it appears unlikely that there is a direct relationship between the two. A more likely cause is the transverse stress concentration caused by the saw cut.
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