Frictional Properties between Sand and Various Construction Materials

The purpose of this research was to determine the frictional characteristics of various bedrocks and construction materials against sand under cyclic loading. Laboratory testing was conducted using a direct shear device which cyclically strained the sand-material interface. The results indicate that the skin friction is a function of the surface roughness of the solid member against the soil. The apparent skin friction approaches the internal angle of friction of the sand as the surface roughness increases. The behavior of sand as tested in a cyclic direct shear test resembles the behavior of sand when tested in small-amplitude dynamic testing devices. No relationship seems to exist between skin friction and the damping ratio. More additional work will be necessary to verify this finding.