Wang Haike, Howard Ken, Peng Jianbing, Qian Hui, Gao Yanyan, Xu Panpan
School of Water and Environment, Chang'an University, Xi'an, 710054, Shaanxi, China.
Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education, Chang'an University, Xi'an, 710054, Shaanxi, China.
Sci Rep. 2024 Mar 25;14(1):7013. doi: 10.1038/s41598-024-57797-2.
The uniformity of remolded loess is crucial for engineering stability and in laboratory testing, as it affects physical and mechanical properties. It is important to have an index which can accurately and conveniently evaluate the uniformity of remolded loess. This study demonstrated and verified the feasibility of using hydraulic conductivity (K) as an indicator for evaluating the uniformity of remolded loess through laboratory experiments and theoretical analysis. In laboratory research, nine loess samples under different preparation conditions were meticulously prepared in duplicate, which were divided into three sets according to the whole dry density (WDD) of approximately 1.3 g/cm, 1.4 g/cm, and 1.5 g/cm respectively. For the nine duplicate samples, two procedures were performed for each of the sample. One is the uniformity analysis by cutting the soil column and weighing. The other is the hydraulic conductivity experiment. Results showed that sample uniformity is affected by sample preparation conditions, and there are differences in the uniformity of the same WDD samples. The values of K positively correlate with the degree of sample uniformity. In theoretical analysis, based on Darcy's Law and Kozeny-Carman equation, it is found K is inversely proportional to the variance ( ) of the sample dry density. That is, K is positively proportional to the sample uniformity. Since K can be easily determined in the laboratory, the application of this new index in the field of geotechnical engineering makes it very convenient and simple to evaluate the uniformity of remolded loess.
重塑黄土的均匀性对工程稳定性至关重要，在实验室测试中，它会影响物理和力学性质。拥有一个能够准确且方便地评估重塑黄土均匀性的指标很重要。本研究通过实验室试验和理论分析，论证并验证了使用渗透系数（K）作为评估重塑黄土均匀性指标的可行性。在实验室研究中，精心制备了九组处于不同制备条件下的黄土样本，每组样本均制备两份，根据大致为1.3 g/cm、1.4 g/cm和1.5 g/cm的干密度（WDD）将其分为三组。对于这九组双份样本，对每个样本都进行了两个步骤的操作。一个是通过切割土柱并称重进行均匀性分析。另一个是渗透系数试验。结果表明，样本均匀性受样本制备条件影响，相同WDD的样本在均匀性上存在差异。K值与样本均匀程度呈正相关。在理论分析中，基于达西定律和柯曾尼 - 卡曼方程，发现K与样本干密度的方差（ ）成反比。也就是说，K与样本均匀性成正比。由于K在实验室中易于测定，该新指标在岩土工程领域的应用使得评估重塑黄土的均匀性变得非常方便和简单。
