DATA of the manuscript 'Modelling Desiccation-Induced Crack Porosity using a VG-based Shrinkage Model and Anisotropic Theory'

This data is exclusively for Catena's peer review process. The abstract of this manuscript is as follows: Clayey soil undergoes shrinkage during desiccation, resulting in a transfer of porosity from within the soil aggregates into cracks. These cracks detrimentally affect the mechanical properties of the soil and alter its hydraulic behaviors by providing preferential pathways for fluid or contaminants. Accurate modelling of desiccation cracks is an essential prerequisite for comprehending crack mechanisms and predicting water movement. However, existing volume-based models often neglect soil subsidence and shrinkage anisotropy. To address this limitation, we developed a model that predicts crack porosity as a function of soil water content that incorporates shrinkage anisotropy. This model was founded on a unified set of governing equations describing the porosities of the matrix, subsidence, and cracking domains. Matrix porosity was estimated using a modified normalized VG-Peng shrinkage model, while shrinkage anisotropy was characterized by a geometric factor (rs) modeled with a logistic function. After validating both sub-models, the integrated crack porosity model that incorporates VG-Peng model and shrinkage anisotropy model was verified. The unified model was tested on both undisturbed and remolded soils using ring-knife samples of 200 cm³ and 500 cm³. The normalized VG-Peng equation exhibited an excellent fit to all experimental data (R² and NSE > 0.95). The evolution of shrinkage anisotropy displayed three distinct phases: initial vertical subsidence, followed by predominant vertical with slight horizontal shrinkage, and finally horizontal cracking. The crack porosity model accurately predicted experimental data across different layer thicknesses using anisotropic shrinkage inputs from both ring-knife types. By integrating shrinkage anisotropy into a volume-based framework, our model achieves higher predictive accuracy than previous approaches.本数据集仅用于Catena期刊的同行评审流程。本文稿件的摘要如下： 黏土在干燥过程中会发生收缩，导致孔隙从土壤团聚体内部转移至裂缝中。这些裂缝会对土壤的力学性能产生不利影响，并通过为流体或污染物提供优先运移通道，改变土壤的水力特性。准确模拟干燥裂缝是理解裂缝形成机制、预测水分运移的必要前提。然而，现有的基于体积的模型往往忽略了土壤沉降与收缩各向异性的影响。为解决这一局限，本研究构建了一个以土壤含水量为变量的裂缝孔隙度预测模型，该模型纳入了收缩各向异性因素。该模型基于一套统一的控制方程，分别描述基质孔隙、沉降域与裂缝域的孔隙度。基质孔隙度通过改进的归一化VG-Peng收缩模型（modified normalized VG-Peng shrinkage model）进行估算，而收缩各向异性则通过采用逻辑函数建模的几何因子（rs）进行表征。在对两个子模型进行验证后，本研究进一步验证了整合VG-Peng模型与收缩各向异性模型的集成裂缝孔隙度模型。本研究采用体积为200 cm³与500 cm³的环刀试样，对该统一模型在原状土与重塑土上的表现进行了测试。归一化VG-Peng方程对所有试验数据均展现出极佳的拟合效果（决定系数R²与纳什效率系数NSE均大于0.95）。收缩各向异性的演化过程可分为三个显著阶段：初始垂直沉降阶段，随后以垂直收缩为主、伴随轻微水平收缩的阶段，最终进入水平裂缝发育阶段。基于两种环刀试样得到的各向异性收缩输入参数，该裂缝孔隙度模型可准确预测不同土层厚度下的试验数据。通过将收缩各向异性纳入基于体积的建模框架，本模型相较于既往方法实现了更高的预测精度。