This study investigates the intrinsic permeability of two water-based transparent soil surrogates (Aquabeads and hydrogel beads) in various aqueous environments. To maximise the efficiency of seepage tests for different solutes (salt and a surfactant) at different concentrations, a rapid approach was established to estimate the intrinsic permeabilities of these water-based granular polymers. Due to the geometric similarity of the pore structures formed by the packing of granular polymer beads of different sizes, the Kozeny–Carman permeability estimation can be directly applied to study the permeability (K), which primarily varies with the effective diameter (d_e). A systematic sieving analysis of these polymers was conducted to determine the values of both d_e and K. The experimental results showed that both parameters monotonically decrease with increasing solute concentration. The critical shrinkage concentrations for salt and the surfactant were identified as 5–7 ppt and 0·02% (mass/volume), respectively. This study represents the first contribution to providing a sound understanding of the intrinsic permeabilities of these surrogate soils when saturated with various solutions. This study contributes to the physical modelling in geotechnics when using those materials.

中文翻译：

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各种水环境条件下透明土的固有渗透率

本研究调查了两种水基透明土壤替代物（Aquabeads 和水凝胶珠）在各种水环境中的内在渗透性。为了最大限度地提高不同浓度的不同溶质（盐和表面活性剂）的渗流测试效率，建立了一种快速方法来估计这些水基粒状聚合物的固有渗透率。由于不同尺寸的粒状聚合物珠粒堆积形成的孔隙结构的几何相似性，可直接应用 Kozeny-Carman 渗透率估计来研究渗透率（K），其主要随有效直径（d _e）而变化. 对这些聚合物进行了系统的筛分分析，以确定两种d的值_e和K。实验结果表明，这两个参数都随着溶质浓度的增加而单调下降。盐和表面活性剂的临界收缩浓度分别确定为 5–7 ppt 和 0·02%（质量/体积）。这项研究首次有助于深入了解这些替代土壤在各种溶液饱和时的内在渗透性。当使用这些材料时，这项研究有助于岩土工程的物理建模。