Abstract: The influence of surface roughness and interface moisture content on the interface shear strength are investigated throughout the interfacial shear test of steel plate and silty clay samples. The significance of factors was compared by using the standardized regression coefficient method. The results show that the greater the roughness, the greater the interface shear strength and its index. With the increase of water content, the interface shear strength and interfacial friction angle gradually decrease, and the interface cohesion first increases and then decreases. The relationship between the interface shear strength and the three independent variables of normal stress, roughness and moisture content conforms to multiple linear regression. Roughness and moisture content have significant effects on the interface shear strength, but the influence of moisture content is greater. The research results can provide a reference value for the interaction between steel piles and silty clay. 

Key words: Steel, Silty Clay, Interface Shear Strength, Roughness, Water Content, Significance Analysis