Mechanosorptive Creep of Norway Spruce on the Tissue Scale Perpendicular to Grain

This dataset contains experimental results from our study (Ferrara and Wittel, 2025b), in which mechanosorptive creep tests were performed on Norway spruce tissue slices in the transverse anatomical directions—radial (R) and tangential (T)—under cyclic relative humidity (RH) between 30% and 90%. Samples were cut in the orientations {RL, RT, TR}, where the first letter denotes the longitudinal dimension and the second the transverse width, all comprising alternating bands of earlywood (EW) and latewood (LW). Tests were carried out at different loading degrees (LD): {RL, RT} at 30% and 50%, and {TR} at 40% of the respective tensile strength. Reference tensile strengths were taken from our earlier work (Ferrara and Wittel, 2024).

The dataset is organized by sample type, with each file containing multiple sheets corresponding to individual experiments. Each sheet reports detailed information about the sample (e.g., dimensions, loading degree, ...), together with time, moisture content, creep strain, and creep compliance measurements. In addition, two CSV files are provided: the first contains mean elastic compliance values from our earlier work (Ferrara and Wittel, 2024), enabling analyses of how creep compliance scales with elastic compliance; the second contains element compliances of the Kelvin–Voigt model describing the mean viscoelastic compliances from our previous work (Ferrara and Wittel, 2025a), which serve as input for calculating the viscoelastic strain component. Finally, one NPZ file includes the results of Dynamic Vapor Sorption (DVS) tests, reproducing the RH profile applied in the mechanosorptive experiments.

A. Ferrara and F.K. Wittel "Mechanosoprtive Creep of Norway Spruce on the Tissue Scale Perpendicular to Grain", Holzforschung (2025b)
A. Ferrara and F.K. Wittel "Tensile Creep of Norway Spruce on the Tissue Scale", Mechanics of Time-Dependent Materials (2025a)
A. Ferrara and F.K. Wittel "Micro-mechanical tests on tissue slices of Norway spruce: tensile and shear performance", Holzforschung (2024)