Experimental Study on Shear Strength of Root- soil Composite of Different Grass and Shrub Plants in Three Gorges Reservoir Region

摘要

This paper discusses the relationship between shear strength of soil-root composite and root content of different plant species. The direct shear test of root - soil composite was made by grass and shrub plants -- alfalfa, Indigofera amblyatha, cynodon dactylon and purple soil. That how plant root system can improve the soil shear strength was analyzed. The results show that the shear strength of reinforced soil is increased. When the same plant root-soil composite is under the same root content, the shear strength is enhanced with the increase of normal stress. The peak value of shear strength appears in 0.4 - 0.5g per 60 cubic centimeters.