Soil and Rock nailing is a construction method used to maintain or enhance the stability of the Soil or Rock by installing reinforcing elements (nails) in accordance with principals for the execution of geotechnical works. Nailing forms a retaining structure of reinforced Soil or Rock mass with which the nail is predominantly subjected to tensile stress. In addition, it may also be subjected to bending and shear stresses.
The design of soil/ rock nailing solutions for slopes generally favor installation angles from 0° - 30° downwards from the horizontal and depending of the stress situation a standard nail drilling pattern of 1 to 3 m c/c in longitudinal and vertical direction for the extent of the slope. Soil nail lengths can normally vary from 4 to 15 meters.
The conventional method of installation involves drilling the self-drilling anchor with air or water flush to the design depth, and then in a second phase, independent of drilling, a grout adapter is added and a cement based grout mix is injected through the hollow core to exit at the bottom of the borehole, and then return upwards to fill the annulus, thus providing once cured for the transfer of tension load from the soil/ rock formation to the self drilling anchor.
Anyhow, using an swivel injection adaptor makes it possible to perform both drilling and grouting simultaneously. Thus is increasing productivity and quality of grouting.