红黏土边坡香根草根土复合体的强度特性

[目的]针对植物护坡效应,探究香根草根系的力学特性及其根土复合体强度特征影响因素,为植物护坡工程设计提供参考依据.[方法]利用模型箱模拟红黏土填筑边坡进行香根草种植,利用根系拉拔试验和原状根土复合体直剪试验等室内试验,研究香根草的力学性能及根土复合体强度特征的影响因素.通过对试验结果进行拟合分析及Spearman相关性...

Strength Characteristics of Vetiver Root-Soil Complex on Red Clay Slope

[Objective] The slope protection effect of plants, the mechanical properties of the root system of vetiver and the factors influencing the strength characteristics of the root-soil complex were studied to provide a reference basis for plant slope protection engineering design.[Methods] First, an outdoor model box was used to simulate the filling of red clay on the slope for vetiver planting conditions, and the mechanical properties of vetiver and the factors influencing the strength characteristics of the root-soil complex were studied through indoor tests, such as a root pull test and undisturbed root-soil composite direct shear test. Through fitting analysis and Spearman correlation analysis of the test results, the relationship between root diameter and tensile properties of vetiver and the effects of different indices on the shear strength of the root-soil complex were obtained.[Results] The average stretching resistance of the vetiver root system was 19.05 N, and the average tensile strength was 20.12 MPa. The stretching resistance and tensile strength of the root system of vetiver had a significant power function relationship with root diameter. Root weight density(RWD)decreased with increasing soil depth. The results of Spearman correlation analysis showed that the RWD and cohesive force c of the root-soil complex had a positive and strong correlation (R=0.882).[Conclusion] As the diameter of the root system of vetiver increases, its tensile strength increases and its tensile strength decreases. The increase in RWD can significantly increase the cohesive force c of the vetiver-red-clay root-soil complex, but the effect of increasing the friction angle φ is not obvious.