To study the shear characteristics of the soil reinforced with herb roots

annual plant Achnatherum splendens roots were adopted as the web of the reinforced soil

and which were planted on the slopes of the test area.The reinforced soil of the roots was divided into nine groups of remolding proof samples according to different root amounts.The shear friction test on the samples showed that:under certain root amount and moisture content

apositive linear relationship was showed between the shear strength of the reinforced soil of roots and the normal pressure of the shear plane

as shear strength increased with the increasing vertical pressure.While under certain moisture content and vertical pressure

shear strength increased with the increasing root amount

cohesion c and internal friction angleφincreased as well

and an exponential relation was showed between cohesion c and root amount

but no significant changes occurred to internal friction angleφ. Exponential relationships were showed between the shear strength of the reinforced soil of the roots and root amount

when the vertical pressure was 20.5

61.5

102.5and 143.5kPa.This study showed that roots of Achnatherum splendens can improve the shear strength in the testing areas and enhance the slope stability.