Static and Dynamic Analysis of Nailed Slope

Abstract

In the present study, slope stability analysis is carried out for a nailed slope with 50° slope angle and 20 m height. Analysis is carried out by both 2D limit equilibrium and finite element methods using a geotechnical modeling software GeoStudio. Sections of slope without and with nails are analysed for stability with respect to static, pseudo-static and dynamic conditions. Dynamic response of nailed slope is analysed against an earthquake with PGA of 0.15 g by finite element method. The acceleration–time history is used as an input to simulate the earthquake in the numerical model. A parametric study is carried out to analyse the effect of nail inclination, nail spacing and nail length on the stability of nailed slope. The variation of factors of safety, shear stresses and displacements during earthquake is also analysed by finite element method using Geo-slope. From the analysis, it is found that the slope is unstable without nails with factor of safety 1.116 in static condition. And the factor of safety increases to about 1.628 by soil nailing. The slope with optimum nail inclination and spacing is analysed for dynamic response. The nailed slope is critical at 7th second of earthquake with factor of safety of 1.35 for an average acceleration 0.124 m/s2. Horizontal displacement of 60 mm is obtained at the top of the nailed slope due to earthquake. The displacements decrease from top to the bottom of the slope.