Soil Nailing Technique

Abstract

The soil nailing is done to treat those natural soil slopes which are unstable in nature. The purpose of our project is to study the technique of soil nailing whether it is apt for soil stabilization or not. . The technique involves the insertion of relatively slender reinforcing elements into the slope – often general purpose reinforcing bars although solid or hollow-system bars are also available. Bars installed using drilling techniques are usually fully grouted and installed at a slight downward inclination. Typical soil nails (Screw and Helical nails) have been used in this project with its various testing of slopes. The comparative study has been performed by using these two types of nails in order to determine which nails give the more stabilised slope. This project serves the main focus in order to replicate the actual conditions of soil nailed structures while using the screw and helical nails. We used prototype model tank with suitable dimensions in order to show our project work of soil nailing. The nails which were used during this project were fitted with foil strain gauge along with soldered copper connecting wires to show the required resistance value. The basic purpose of finding this resistance value was to convert it into the required strain value exhibited between soil and nail and it was done by using a suitable formula discussed later in this report. The experimentation was performed by using soil slopes of 45˚, 60˚, 90˚ with nail inclination of 15˚ and 30˚. Our results and discussions shows it clearly that screw and helical nails give better load bearing capacity when being compared to drilling nails. This is because there is no such case of disturbance of normal strata of soil and its slope in screw and helical nails. The plotting of various graphs shows the behaviour of our model testing w.r.t different slope angle which depicts the actual scenario of soil nailed structures inclined at specific angle. Keywords: Screw Nails, Helical Nails, Soil Nailing, Slope Stabilization.