Effect of the influence of Medicago sativa L. root area ratio on slope stability

doi:10.16178/j.issn.0528-9017.20240384

Abstract

Abstract:

Slope protection projects have attracted much attention in recent years. Ecological slope protection based on herbaceous plants such as Medicago sativa L. has gradually become the first choice for slope protection projects. Based on the collected direct shear test data of Medicago sativa L. roots, the correlation between root area ratio (RAR) and the increase of soil cohesion (Δc/c₀) and the increase of internal friction angle (Δφ/φ₀) was preliminarily discussed by correlation analysis method. The finite element software PLAXIS 3D was used to simulate the slope, and the variation law of slope safety factor and total displacement under different RAR was studied. The results showed that Medicago sativa L. can increase the cohesive force of the slope and thus effectively reinforce the slope and improve the stability of the slope, and there was an optimal root area ratio of 0.3%. At this time, the root system had the best reinforcement effect on the slope soil. This study can provide reference for ecological soil reinforcement of shallow slope.

Key words: Medicago sativa L., root area ratio, cohesive force, PLAXIS 3D, numerical analysis

CLC Number:

S541.9

LIU Chen, LYU Yi, GAO Xinnan. Effect of the influence of Medicago sativa L. root area ratio on slope stability[J]. Journal of Zhejiang Agricultural Sciences, 2026, 67(1): 178-183.

Figures/Tables 5

Fig.1 Fitting relationship between RAR and the increase of soil cohesion (a) and internal friction angle (b)

Fig.2 Slope geometric model

Fig.3 Slope safety factors under different root area ratios

Fig.4 Distribution cloud diagram of slope deviatoric strain increment under different RAR

Fig.5 The relationship curve between the root area ratio and the total displacement of the slope

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