A New Type DSS Device and Its Application in Shaft Friction of Pile in Soft Rock

Soft rock is extensively distributed worldwide, and the piles in the soft rock are widely used in high- rise buildings and bridge engineering with high loads and high settlement requirements. The soft rock- socketed pile differs from the hard rock and soil pile in terms of failure mode and interface characteristics. The pile-rock interface of piles in soft rock features an expansion slip and normal constant stiffness. Direct simple shear is more consistent with the actual case than direct shear in stress and deformation. Based on this, a new type of DSS apparatus with constant stiffness is developed to study the interface of pile-soft rock. The shear test of soft rock and pile-soft rock interface with different roughness is carried out, and the rationality of the test method is demonstrated. Combined with the reasonable generalization of the roughness of the interface, an indoor test method for obtaining the shaft friction of a pile in soft rock can be proposed.