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arXiv · 2507.01071

Orthotropic Viscoelastic Creep in Cellular Scaffolds

Alessia Ferrara·Falk K. Wittel
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Abstract

Recent measurements of Norway spruce have revealed stress-state-dependent normalized creep behavior, highlighting a gap in our fundamental understanding. This study examines whether the anisotropic response originates from the micro-structural, cellular nature of composite cell walls with varying tracheid types. Cell wall creep parameters are identified via surrogate-based inverse parameter identification, applied to hierarchical micro-mechanical and FEM models of increasing topological complexity up to the growth ring scale. Despite microstructural disorder, simulated creep curves converge toward a universal set of proportionality factors. The results indicate that directional creep behavior cannot be attributed solely to tissue-scale topology, and that realistic predictions require the inclusion of non-linear material responses at stress concentration sites.

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Alessia Ferrara, Falk K. Wittel. 2025-07-01. Orthotropic Viscoelastic Creep in Cellular Scaffolds. https://arxiv.org/abs/2507.01071

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