Tensile Creep Tests on Tissue Slices of Norway Spruce

This dataset presents experimental results from our work (Ferrara and Wittel, 2025), where creep tests were conducted on tissue slices of Norway Spruce in different anatomical orientations—longitudinal (L), radial (R), and tangential (T)—under varying relative humidity (RH) levels of 30%, 65%, and 90%, corresponding to moisture contents of 0.07, 0.12, and 0.2, respectively. The tissue samples were sliced in all orientations: {LR, RL, RT, TR, LT}, where the first letter indicates the longest dimension and the second represents the width. The {LR, RL, RT, TR} samples feature alternating bands of earlywood (EW) and latewood (LW). For the LT samples, distinct tissues were isolated for EW and LW: {LT-EW, LT-LW}. The tests were conducted at two different loading degrees (LD), 30% and 50% of the tensile strength for each case. Reference values for tensile strength were taken from our previous work (Ferrara and Wittel, 2024).

The dataset is organized by sample type, with each file containing multiple sheets, one for each experiment. Each sheet provides detailed information about the sample, including its dimensions, RH during the experiment, applied load, and loading degree. Moreover, time, creep strain, and creep compliance measurements are recorded for each test.

The dataset also includes four CSV files. One contains the elastic stiffness values determined in our previous work (Ferrara and Wittel, 2024), which are useful for studying how creep compliance scales with elastic compliances. The remaining three files contain the results of the DVS tests on earlywood, latewood, and transition wood tissue, reported in the appendix of our work (Ferrara and Wittel, 2025).

A. Ferrara and F.K. Wittel (2025), "Tensile Creep of Norway Spruce on the Tissue Scale"
A. Ferrara and F.K. Wittel (2024), "Micro-mechanical tests on tissue slices of Norway spruce: tensile and shear performance"

本数据集收录了本团队2025年研究（Ferrara与Wittel，2025）的实验结果，该研究针对挪威云杉（Norway Spruce）组织切片开展了蠕变试验。试验设置了三种不同的解剖学取向：纵向（longitudinal, L）、径向（radial, R）与切向（tangential, T），并采用30%、65%、90%三种相对湿度（relative humidity, RH）水平，对应含水率分别为0.07、0.12与0.2。
所有样本均按以下取向进行切片：{LR、RL、RT、TR、LT}，其中第一个字母代表最长维度的方向，第二个字母代表样本宽度方向。其中{LR、RL、RT、TR}样本具有早材（earlywood, EW）与晚材（latewood, LW）交替的条带结构；对于LT样本，我们分离得到了单独的早材与晚材组织，即{LT-EW、LT-LW}。
本试验设置了两种加载水平（loading degree, LD），分别为对应工况下抗拉强度的30%与50%。抗拉强度的参考值取自本团队2024年的前期研究（Ferrara与Wittel，2024）。
本数据集按样本类型进行分类组织，每个文件包含多个工作表，每张工作表对应一次独立试验。每张工作表记录了样本的详细信息，包括尺寸、试验过程中的相对湿度、施加荷载以及加载水平；此外，每次试验均同步记录了时间、蠕变应变与蠕变柔量的实测数据。
本数据集还包含四个CSV格式文件：其中一个文件收录了本团队2024年研究中测得的弹性刚度值，该数据可用于探究蠕变柔量与弹性柔量之间的缩放关系；剩余三个文件分别收录了针对早材、晚材与过渡木组织开展的DVS测试结果，相关内容已在本团队2025年研究的附录中予以汇报（Ferrara与Wittel，2025）。
A. Ferrara与F.K. Wittel（2025），《挪威云杉组织尺度下的拉伸蠕变性能》（Tensile Creep of Norway Spruce on the Tissue Scale）
A. Ferrara与F.K. Wittel（2024），《挪威云杉组织切片的微力学测试：拉伸与剪切性能》（Micro-mechanical tests on tissue slices of Norway spruce: tensile and shear performance）