Experimental Determination of Best Angle for Soil Nailing

• Author(s): Ikechukwu Solomon Utobuiro ; Obianyo Chidubem Collins Augustine ; Gerald Chekwube Ezeamii
• Paper ID: 1704662
• Page: 1523-1543
• Published Date: 30-06-2023
• Published In: Iconic Research And Engineering Journals
• Publisher: IRE Journals
• e-ISSN: 2456-8880
• Volume/Issue: Volume 6 Issue 12 June-2023

Abstract

Soil nailing is a soil stabilization technique which is used as a remedial measure in order to treat the unstable natural or artificial soil slopes. This technique is also used in order to allow the safe over-steepening of new or existing soil slopes. In this method of slope stabilization, a relatively slender reinforcing element is driven into the soil slope. Reinforcing elements generally used in this technique generally consists of HYSD (High yielding strength deformed) steel bars or steel hollow tubes depending upon the requirement. The nails used for soil nailing are generally driven into the slope at an angle of 10to 20 with horizontal plane. Due to the application of surcharge load by various means, the backfill material starts deforming which in turn passively produces the tensile stresses in the nails. The method of installation is different for solid and hollow bars. Solid bars are generally installed into the pre-drilled holes. These bars are grouted into place simultaneously using separate grout line. Hollow bars are drilled and grouted simultaneously with the help of “sacrificial” drill bit. In recent years, soil nailing has been widely used to stabilize the steep slopes or carryout ground improvement. It involves the use of passive inclusions, usually steel bars (known as soil nails), to reinforce in-situ retained ground. The installation of the soil nails is progressive and is carried out simultaneously with soil excavation in front of the retained wall. This takes place in a series of successive phases (US Federal Highway Administration, 1999). The majority of slope stability analyses performed in practice still use traditional limit equilibrium approaches involving methods of slices and calculating the factor of safety. Documented failures of soil – nailed systems for the most part are non – existent in the literature, and a few full – scale and model testing research programs has been conducted. (Kitamura et al. 1988) studied the effect of steel bar reinforcement in vertically loaded reinforced sand slopes. A number of small-scale model tests of reinforced slopes are conducted by (Gutierrez and Tatsuoka 1988) to measure the tensile reinforcement forces and strain fields. Similarly a series of model tests are performed by (Hayashi et al. 1990) to investigate the failure mechanism of steel bar reinforced cut slopes. (Huang and Tatsuoka 1994) analyzed the results of a series of plane strain model tests for both reinforced and unreinforced sand slopes loaded with a 10 m wide strip footing. Model tests to investigate the effects of surcharge loading on the failure mechanism of soil-nailed structures are performed by (Drabkin et al. 1995). (Long et al. 1990) studied the importance of variables like the shape of the assumed failure surface, wall height, inclination, length of nails and global stability of nailed soil wall.

Citations

IRE Journals:
Ikechukwu Solomon Utobuiro , Obianyo Chidubem Collins Augustine , Gerald Chekwube Ezeamii "Experimental Determination of Best Angle for Soil Nailing" Iconic Research And Engineering Journals Volume 6 Issue 12 2023 Page 1523-1543

IEEE:
Ikechukwu Solomon Utobuiro , Obianyo Chidubem Collins Augustine , Gerald Chekwube Ezeamii "Experimental Determination of Best Angle for Soil Nailing" Iconic Research And Engineering Journals, 6(12)