We prepare to rebuild slope project′s stratum

which consists of the quaternary slope sediment in surface and silurian phyllite metamorphic rock.In order to identify the mechanical properties of the proposed slope of rock

we selected two typical areas for big shear experiments.The results showed:field shearing test can objectively reflect the basic characters and actual situation of the experimental subject;shear properties and shear compression and dilation of strongly weathered phyllite is related to their degree of weathering and integrity features of rock

and when the integrity features of rock is well and the degree of weathering is low

the rock mechanical properties is significant

the shear failure is brittle failure shows sustained dilatancy;when the weathering is bad

broken rock shows some mechanical properties of the soil

the shear failure is plastic failure and the performance is first compression then dilation;the shear strength of the gravel soil is related to the amount of gravel

when it is larger

the shear strength is higher

its performance is in dilatancy under low normal stress

and under high normal stress

its performance is first compression then dilation.By using shear strength parameters obtained by different methods to analyze slope stability

the results obtained in the large direct shear test in the field are more helpful to the slope stability analysis and engineering design

and provide a scientific basis for slope stability analysis and design.