Abstract

Studying the pullout characteristics of roots can help to gain a deeper understanding of the interaction mechanism between plants and soil, and provide theoretical support and practical guidance for engineering applications. This paper aims to investigate the pulling characteristics of the root–soil interface in expansive soil reinforced by vetiver roots. For this purpose, the study focuses on exploring the correlation between the pullout force (PF) required to extract the roots and the pullout displacement caused by the extraction. The research also examines how the geometry of the roots affects the pulling characteristics of the root–soil using a pullout test. It is found that with increasing root diameter, root length segment (RLS), root volume, and root surface area (RSA), the maximum PF increases. The highest correlation coefficient was found between RSA and maximum PF, which explained 81.4% of the variation in maximum PF. Then, the functional relationship between RLS and PF is established. Using RSA to predict the maximum PF of vetiver root is relatively reasonable. The assessment of PF must consider RSA indicators. The increase in RSA due to a high number of roots results in the improvement of the PF of vetiver root. These findings could assist in enhancing the strength of expansive soils.

中文翻译：

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膨胀土中香根草根系抗拔性特征及影响因素研究

摘要

研究根系的拔出特性有助于更深入地了解植物与土壤的相互作用机制，为工程应用提供理论支持和实践指导。本文旨在研究香根草根加固膨胀土中根-土界面的拉力特性。为此，研究重点探讨拔除根所需的拔出力（PF）与拔除引起的拔出位移之间的相关性。该研究还通过拉拔试验研究了根部的几何形状如何影响根部-土壤的拉拔特性。研究发现，随着根直径、根长度段（RLS）、根体积和根表面积（RSA）的增加，最大PF增加。 RSA 和最大 PF 之间的相关系数最高，这解释了最大 PF 变化的 81.4%。然后，建立RLS和PF之间的功能关系。利用RSA来预测香根草根的最大PF是比较合理的。 PF的评估必须考虑RSA指标。由于大量根而导致 RSA 的增加导致香根草根的 PF 提高。这些发现可能有助于增强膨胀土的强度。