Parametric assessment of soil-nailing retaining structures in cohesive and cohesionless soils

Soil nailing is an effective stabilizing method for slopes and excavations and has been widely used worldwide. It is a reinforcing method using the shear strength of in-situ ground and the pull-out resistance of soil nailing. Research on numerical schemes of soil-nailing retaining structures has been quite intensive in the past three decades. ‘Plaxis’ finite-element modelling software is very commonly used for numerical simulations. There are difficulties associated with accurately modelling behaviours of these structures in both cohesive and cohesionless soils. Hence, in the present study, the significant influence of the shear strength of soil-nail cut and of the amount of surcharge on the structural behaviour of soil-nailing retaining walls is discussed. The results show that the soil’s physical properties and surcharge directly influence the soil-nailing structures. Another important conclusion is that a soil-nailing structure consisting of nails and tiebacks can be considered a good alternative to improve the safety of excavation walls due to its satisfactory behaviour in the numerical simulations.