Three dimensional finite element analysis of soil nails in granitic soils

Soil nailing techniques have been widely employed in the civil engineering industry to improve the safety margin of soil slopes and excavations. In this paper, a three dimensional finite element model (FE) is developed to simulate the nail-soil interaction of soil nail during shear-box pull-out test under different overburden pressures. The behaviour of soil-nail and its interaction play an important role in overall and internal failure mechanism. The stress strain behaviour of the soil was modelled by the modified Drucker-Prager/Cap model and the interaction between the nail and soil was simulated using a penalty-type interface. The results indicate that soil nail capacity is heavily influenced by the soil-nail interaction mechanism and the shear strength developed at the soil-nail interface.