根土复合体三轴剪切试验研究

Riaxial Shear Tests Study on Root-soil Composite

利用三轴试验仪对夹竹桃根土复合体进行固结不排水试验。对根土复合体的应力-应变关系及抗剪强度指标进行研究,分析了根土复合体的破坏荷载及根土复合体在剪切过程中的阻抗机理。试验结果表明:1根土复合体强度和抵抗变形的能力较素土有显著的增强;2根土复合体的黏聚力和内摩擦角都有所提高,其中黏聚力增长十分明显;3根系布置方式对根土复合体强度增长有影响,复合体强度增长顺序为混合放置>相交放置>竖直放置>水平放置>倾斜放置。研究结果对于深入研究植被护坡机理和指导植被护坡工程设计具有十分重要现实意义。

The consolidated undrained triaxial tests were implemented on the Nerium indicum root-soil compos- ites to reveal the stress-strain relationship and shearing strength index. It also analyzes the failure load and frictional mechanism of root-soil composite in the shearing process. The results show that： ① the strength and the capacity for resisting the deformation are better than those of unreinforced soil; ② the internal friction angle increases while the cohesion improves remarkably; ③the reinforcement effects of soils with different roots layout can be sorted in descending order as ： complex roots layout 〉 intersected roots layout 〉 vertical roots layout 〉 horizontal roots layout 〉 tilted roots layout. The results are of great significance for understanding the mechanism and the design of vegetation protection for slopes.