An Experimental Study of a Nailed Soil Slope: Effects of Surcharge Loading and Nails Characteristics

Abstract

The earth nailing system is a ground improvement technique used to stabilize earth slopes. The behavior of the earth nailing system is dependent on soil and nailing characteristics, such as the spacing between nails, the orientation, length, and method of installation of nails, soil properties, slope height and angle, and surcharge loading, among others. In the present study, a three-dimensional physical model was built to simulate a soil nailed slope with a model scale of 1:10 with various soil nail characteristics. The simulated models consist of Perspex strips as facing and steel bars as a reinforcing system to stabilize the soil slope. Sand beds in the model were formed, using a sand raining system. The performance of nailed soil slope models under three important nails characteristics, i.e., length, spacing and orientation, with varying surcharge loading were studied. It was observed that there is a reduction in the lateral movement of slope and footing settlements with an increase in length. It was found that the slope face horizontal pressure is non-linear with different nail characteristics. The increase in length and inclination of the soil nails decreased the vertical, horizontal stress and footing settlement, while the increase in spacing of the nails increased the vertical and horizontal stress behind the soil mass.

Finite Element Modeling of the Soil-Nailing Process in Nailed-Soil Slopes

“…The laboratory model of the soil-nailing process (total soil slope model with a length of 1760 mm and a height of 850 mm) was completed in nine sequential stages [36], as follows (Figure 1).…”

“…Table 4. Nailed-soil slope geometry parameters in the laboratory model [36]. Slope facing and foundation can be modeled in PLAXIS software by beam elements.…”

Geotechnical Characterization of Quito’s North-Central Zone as Applied to Deep Excavation in the Urban Setting

“…However, the forces obtained with Hardening Soil and HSs have some similarities between them for most of the process, with the Hardening stresses being slightly higher in most of the construction phases, as can be seen in Fig 23 . Accurately estimating the maximum tensile strength that a Soil Nail can sus throughout its service life is a crucial aspect of the final design of a Soil Nailing struct This step considers the ultimate limit states of the pullout and tensile strength of the Nails [76]. Achieving precision in estimating the pullout capacity of a Soil Nail is essen to ensure a cost-effective, efficient, and safe design [77,78]. Therefore, it underscores importance of adopting an appropriate soil constitutive model for the geotechnical a ysis of a Soil Nailing structure.…”

“…This step considers the ultimate limit states of the pullout and tensile strength of the Soil Nails [76]. Achieving precision in estimating the pullout capacity of a Soil Nail is essential to ensure a cost-effective, efficient, and safe design [77,78]. Therefore, it underscores the importance of adopting an appropriate soil constitutive model for the geotechnical analysis of a Soil Nailing structure.…”