To study the shear property of weathered schist residual soil

in-situ direct shear tests was carried out at a slope project in northwest mountain area of Hubei province; and the structural composition

fracture characteristics

relationship of stone ratio and waviness and so on were analyzed. The results show that: The stress and strain curves show strain hardening features

and no obvious peak. The lonely stone and cluster stones are rolling and gnawing fracture in shear surface. There is an approximate linear relationship between waviness of shear surface and stone ratio; and the value of waviness increases with the increase of stone ratio. The climbing effect may cause shear dilation and increase of shear stress and normal stress. With increase of normal stress

the failure mechanism in shear surface turns sliding into gnawing fracture; and the ratio of shear-normal stress is in decrease. The results can be referenced for deformation and stability analysis of slope projects.