Mechanisms of root reinforcement in soils: an experimental methodology using four-dimensional X-ray computed tomography and digital volume correlation
Mechanisms of root reinforcement in soils: an experimental methodology using four-dimensional X-ray computed tomography and digital volume correlation
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DOI：
10.1098/rspa.2019.0838
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发表时间：
2020-05-27
影响因子：
3.5
通讯作者：
Bengough, A. G.
中科院分区：
文献类型：
--
作者：
Bull, D. J.;Smethurst, J. A.;Bengough, A. G.
铁路或公路边坡上的植被可以通过植物蒸腾作用产生土壤孔隙水吸力和根部机械加固土壤来提高边坡稳定性。为了将根部加固土的增强抗剪力和刚度纳入稳定性计算中，有必要了解和量化其有效性。这需要综合而复杂的实验和多尺度建模方法，以加深对不同长度尺度上的过程的理解，从单个根-土壤相互作用到完整的土壤剖面或坡度尺度。多尺度模型的挑战之一是确保它们足够接近地代表真实行为。这需要针对详细的高质量和数据丰富的实验进行校准。这项研究提出了一种新颖的实验方法，它将柳根加固土壤的原位直接剪切载荷与 X 射线计算机断层扫描相结合，以捕获剪切区内土壤和根部变形的三维年代学。将数字体积相关（DVC）分析应用于计算机断层扫描数据集，以获得全场三维位移和应变信息。本文论证了根系强化土壤 DVC 实验的可行性并讨论了相关挑战。
Vegetation on railway or highway slopes can improve slope stability through the generation of soil pore water suctions by plant transpiration and mechanical soil reinforcement by the roots. To incorporate the enhanced shearing resistance and stiffness of root-reinforced soils in stability calculations, it is necessary to understand and quantify its effectiveness. This requires integrated and sophisticated experimental and multi-scale modelling approaches to develop an understanding of the processes at different length scales, from individual root-soil interaction through to full soil-profile or slope scale. One of the challenges with multi-scale models is ensuring that they sufficiently closely represent real behaviour. This requires calibration against detailed high-quality and data-rich experiments. This study presents a novel experimental methodology, which combines in situ direct shear loading of a willow root-reinforced soil with X-ray computed tomography to capture the three-dimensional chronology of soil and root deformation within the shear zone. Digital volume correlation (DVC) analysis was applied to the computed tomography dataset to obtain full-field three-dimensional displacement and strain information. This paper demonstrates the feasibility and discusses the challenges associated with DVC experiments on root-reinforced soils.