植被根系对土体抗剪强度影响的试验研究

以狗牙根为研究对象,分析了实验用土的液塑限、最大干密度、最优含水量;采用单因素法设计,分别使用竖直、水平、与水平方向成30°3种方式向试样中放置根丝进行GDS三轴试验,绘制了试样的应力应变曲线和包络图,分析了狗牙根加筋土主应力差与轴向应变的关系。结果表明:素土及含根土围压-偏应力间呈线性关系;根丝植入对有效内摩擦角φ影响较小;根丝水平放置、倾斜放置时对试样粘聚力c影响较小,竖直放置时对c值有明显增强作用。这是由于水平和倾斜的放置方式,减少了样品的有效受剪区域。

The Experimental Study on the Effect of Vegetation Root on the Soil Shear Strength

Taking bermudagrass as the research object,the author analysis the liquid plastic limit,maximum dry density,optimum moisture content of the experimental soil,adopt the single-factor method,what the GDS triaxial tests have been carried out in three ways: the vertical,horizontal,and horizontal direction at 30°.The author also draw the stress-strain curves,the envelope diagram of samples,and analysis the relationship of bermudagrass reinforced earth principal stress difference and the axial strain.The results show that prime soil and soil containing the root of their confining pressure-linear relationship between deviator stress;implantation of the root less impacted on the effective internal friction angle φ;The root has little impact on the cohesion of soil when they are placed horizontally or aslant,however,the vertical placement is much more effective.It is due to the horizontal and the inclined position reduces the effective shear area of samples.