Parametric Assessment of Soil Nailing on the Stability of Slopes Using Numerical Approach

Abstract

This study focuses on the stability analysis of slopes reinforced by soil nailing. The effects of slope geometry and nail parameters on slope stability are investigated using PLAXIS 2D. Four different slope angles and three different backslope angles are considered for assessing the effect of slope geometry on the stability of a nailed slope. The factor of safety (FS) was found to decrease with the increasing values of the slope angle as well as the backslope angle. The influence of different nail parameters (nail inclination, nail length, and nail spacing) was also investigated. With the increase in nail inclination, FS was found to increase initially and thereafter, reaching a peak value followed by a drop in FS. The optimum nail inclination was found between 0 and 25° at a horizontal angle, depending on the different slope geometries, which is evident from observation of the slip surface as well. With the increase of nail length, FS increases; however, the increase was small after L/H (length of nail/height of slope) reached a value of 0.9. Moreover, increasing the length of the nail was found to be effective in reducing the lateral movement of the slope. The maximum nail forces are observed in the bottom-most row of nails and increase with the depth. The inclusion of soil nailing with optimum nail parameters can increase FS by 29–75% depending on the slope geometry, signifying the effectiveness of nailing.

Slope Stability and Reliability Analysis of Earth Embankment Constructed for the Doubling of Railway Track

“…Commercially available finite element tool PLAXIS 2D has been employed extensively for assessing the stability of soil nailed slopes (Babu and Singh, 2009;Moniuddin et al, 2016;Sharma and Ramkrishnan, 2020;Benayoun et al, 2021;Gui and Rajak, 2024). Elahi et al (2022) employed PLAXIS2D for the parametric study of soil nailed slope through numerical analysis and geometric parameters, such as, slope angle, back-slope angle, soil nail length, spacing and inclination were varied. Results indicated that maximum benefit in terms of enhanced stability is achieved when the nail inclination is in the range of 0-25 degrees from the horizontal, depending on the slope geometry.…”

A Numerical Study of a Soil-Nail-Supported Excavation Pit Subjected to a Vertically Loaded Strip Footing at the Crest

“…A zero-thickness interface element represented the interface between the grout and the soil. Elahi et al [7], Rawat and Gupta [27], and Jaiswal and Chauhan [28] used an interface with a thickness of 0.1 mm in their studies. The roughness or the strength of the soil/grout interface is defined by the strength reduction coefficient R inter , which can be calculated as…”

“…Elahi et al [7] conducted a series of parametric studies using Plaxis 2D to study the effect of nail installation angles and observed that the optimum nail inclination angle was between 0 and 25 • . A similar study was performed by Amrita et al [8], who studied the effect of nail length, nail inclination, and different site conditions using Plaxis 2D and concluded that the optimum nail angle was 15 • and that the longer the nail length, the more stable the slope was.…”

Numerical modelling of cut-slope stability in the Lesser Himalayan terrain of west-central Nepal

“…Nowadays, soil nailing is widely used as a reinforcement technique to improve the stability of steep slopes and vertical cuts (Fan and Luo, 2008;Jaiswal et al, 2022;Lin et al, 2013;Pandey et al, 2021;Zhang et al, 2014). The increase of L/H (ratio of soil nail to height of the slope) from 0.5-0.9 increases the factor of safety by 16.2-33.8% for slopes varying within 45°-90°, whereas the increase of L/H from 0.9-1.2 increases the factor of safety by only 1.7-4.3% (Elahi et al, 2022).…”