鲱骨状根构型对典型土体抗倾覆力的有限元分析

 设计和实施治理重力侵蚀的生物工程措施需要深入地分析和研究树木根系对土体的抗倾覆力学特性。本文以单株鲱骨（Herringbone）状根构型为研究对象建立二维有限元模型,通过控制侧根与主根的夹角、删减根系不同部分等方法,建立了12种不同几何形态的鲱骨状根结构,并分别验证其在黏土和砂土中的抗倾覆力,由此定量评价根系的不同部分和土壤的差异分别对土体抗倾覆力的贡献率。模拟结果显示:浅层侧根的作用是不可低估的,在黏土中,其贡献率约占整个固土效果的35%40%;根、土复合体在整个破坏过程中形成一个旋转轴,此轴的位置随根系形态、土壤类型的不同而变化。

Finite element analysis of herringbone-like root anchorage in representative soil types

A better understanding of root-soil mechanical interaction is necessary for investigating the capability of structural roots to provide an efficient anchorage of root or to participate to soil fixation against landslides and soil erosion. This paper aims in analysing the contribution of different root elements and soil types to root anchorage. For this purpose, a 2D finite element model of root anchorage has been built up and applied to twelve different herringbone-like root patterns. These root patterns have been defined varying the angle between lateral root and main root, and removing different root parts. Bending tests has been performed in both clay and sandy soil. Numerical results showed that shallow lateral roots play a significant role in root anchorage, contributing nearly 35 % - 40 % to the root-soil strength in the whole simulations. Moreover, it was shown that root architecture and soil type can significantly modify the hinge of root plate rotation axis.