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1. JAWHAR LAL NEHRU NATIONAL
COLLEGE OF ENGG
DEPARTMENT OF CIVIL ENGINEERING
SOIL NAILING
GUIDED BY : PRESENTED BY
Mr.UMAPATHI PUNEETH M S
Asst.Professor M.Tech 1st Sem
Dept.of Civil Engg

2. INTRODUCTION
• Soil nailing is a technique used
to reinforce and strengthen
existing ground.
• Soil nailing consists of installing
closely spaced bars into a slope
or excavation as construction
proceeds from top down.
• It is an effective and economical
method of constructing retaining
wall for excavation support,
support of hill cuts, bridge
abutments and highways.

3. SCOPE AND OBJECTIVE
Soil nails can provide the best technical and economical
solution for the repair and the strengthening of existing
retaining structures.
• To study the favourable ground conditions, components,
types, machineries used, materials used in soil nailing.
• To study the design requirements ,limit state for soil nailing.
• To study the construction sequences for soil nailing.

4. FAVOURABLE UNDER-GROUND
CONDITIONS
• The excavated soil should be able to stand unsupported in 1m-
2m high vertical cut for maximum 2 days
• Soil nails should be located above the ground –water table
• The ground conditions should allow drill holes to be advanced
without using drill casings

5. COMPONENTS OF A SOIL NAIL WALL

6. TYPES OF NAILS USED
• Drilled and Grouted Soil Nail: Approximately 100-200mm in diameter.
Spaced at about 1.5m apart.
• Driven Soil Nails: Relatively small in diameter about 19 to 25mm.Spaced
at approx 1 to 1.2m apart. Mechanically driven. Allows faster installation
• Self Drilling Soil Nails: Consist of hollow bars which can be drilled and
grouted in one operation. Allows faster installation than drilled grouted
nails and provides corrosion protection
• Jet-Grouted Soil Nails: First step, allows advancement of the nail to the
final location. In second step, the bars are installed using vibro-percussion
drilling methods
• Launched Soil Nails: Bare bars are launched into the soil using a firing
mechanism. Bars are 19 to 25mm in diameter and 8m in length.

7. MACHINERIES USED
Typical
drilling
equipment
Grout Mixing
Instrument
Shotcreting is done
using a pipe

8. DESIGN REQUIREMENTS
• After a preliminary analysis of
the site, initial designs of the
soil nail wall can be begin.
• This begins with a selection of
limit states and design
approaches.
• The two most common limit
states used in soil nail wall
design is strength limit and
service limit states.

9. LIMIT STATES
• The strength limit state is the limit state that addresses
potential failure mechanisms or collapse states of the soil nail
wall system.
• The service limit state is the limit state that addresses loss of
service function resulting from excessive wall deformation and
is defined by restrictions in stress, deformation and facing
crack width under regular service conditions.

10. CONSTRUCTION SEQUENCES
1. Excavation
2. Drilling nail holes
3. Installation and grouting
nails
4. Construction of temporary
shotcrete facing
5. Construction of subsequent
levels
6. Construction of a final,
permanent facing

11. ADVANTAGES
• It is ideal for tight spaces.
• It can be used in irregular shapes.
• Less noise and fewer traffic obstructions.
• Can be used to repair other existing wall systems.
• It can be used on new constructions, as temporary structures or
on remodeling process.
• Wall height is not restricted.
• Reduce right of way requirements.

12. DISADVANTAGES
• In some instances soil might be overexposed prior to the
installation of nail.
• Sand and gravels might not be compatible with soil nailing.
• Not recommended to use in high water table areas.
• Soil nailing in very low shear strength soil may require a very
high soil nail density.
• Soil nailing in expansive soils and sensitive soils for
permanent long term applications is not recommended.

13. APLLICATIONS
• Stabilization of railroad and highway cut slopes..
• Tunnel portals in steep and unstable stratified slopes.
• Construction and retrofitting of bridge abutments.
• Stabilizing of existing over-steep embankments.
• Road widening under existing bridge abutment.
• Temporary support can be provided to excavations without the
need for bulky and intrusive scaffold type temporary works
solution.

14. CONCLUSION
Soil nailing is embraced by practicing engineers as highly
competitive well proven technique. Soil nailing has certain
similarities to both reinforced earth and anchoring, although its
particular operating principles and constructions methods give it
a firm and distinct identity. similar considerations distinguish it
from allied insitu soil reinforcing techniques such as reticulated
root piles and soil dwelling. Most applications of soil nailing to
date have been associated with new construction projects such
as foundation excavation and slope stabilization, for both
temporary and permanent works.

15. REFRENCES
• International journal of engineering research and general
science volume 3 theoretical analysis of soil nailing ISSN
2091-2730
• FWHA(2003) soil nail walls geotechnical engineering circular
no 7 report no FHWA0-IF-03-017, Fedaral Highway
Administration
• Soil nailing for stabilization of steep slopes near railway
Tracks, prepared by Dr. Amit Prashant, Ms Mousumi
Mukherjee, Department of civil Engineering Indian institute of
technology Kanpur submitted to research designs and
standards organization (RDSO), Lucknow