Abstract
The lasting plastic deformation of the cellular elements of beech, fir, and spruce wood under uniaxial compression has been investigated by the combination of in situ loading and synchrotron micro-computed tomography. The deformation of singular elements embedded in the tissue and their influence on the deformation lines and surrounding tissue was examined by tomographic reconstructions. An automatic observation of the failure area was applied in the case of the softwoods, which permitted the determination of the densification degree. The development of failure lines differed from the expected pattern by often showing branching. However, the 3D observations confirmed the effects known from 2D examinations in many cases.
Acknowledgments
The main author wants to thank the staff at the TOMCAT beamline (PSI) for their helpful support and the technical and mechanical assistance during beam times. Additionally, the main author wants to thank all colleagues who helped with the measurements during beamtimes. This work was supported by the European Cooperation in the field of scientific and technical research (COST, Action FP0802).
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