The document describes an experimental study comparing the ultimate load capacity of soil nailing walls with horizontal nails versus inclined nails in cohesionless soil. The study involves constructing small-scale soil nailing walls in a laboratory tank using steel bars as nails in poorly graded sand at 50% relative density. Nail inclination angles of 10 and 15 degrees will be tested and compared to horizontal nailing (0 degrees). The length-to-height ratio of nails will also be varied. Maximum load will be measured at failure. Analytical calculations of factor of safety for soil nailed walls will also be performed and compared to experimental results. The goal is to evaluate how nail inclination and length-to-height ratio affect ultimate load capacity.

1. EXPERIMENTAL STUDY FOR COMPARISON OF ULTIMATE LOAD IN
COHESIONLESS SOIL BY SOIL NAILING – HORIZONTAL V/S
INCLINED NAILED
Dharmsinh Desai University,
Faculty Of Technology
Nadiad
Prof. Samirsinh P Parmar
Asst. Professor,
Department of Civil Engineering
Mail: samirddu@gmail.com

2. OUT LINE OF PRESENTATION
2
Introduction
Literature Review
Analytical Study
Experimental Study
Conclusion
Future Scope
References

3. INTRODUCTION
 Soil nailing is the method of reinforcing the soil with steel bars or other material.
 It has been alternative technique to other conventional supporting system as it offers
flexibility, rapid construction & competitive cost.
 The purpose is to increase the Tensile & Shear Strength of the soil & Restrain its
displacements.
 Soil nailing is a construction technique used to reinforce soil to make it more stable.
 In this technique, soil is reinforced with slender elements such as reinforcing bars
which are called as nails. These reinforcing bars are installed into pre-drilled holes
and then grouted.
3

4.  Soil nailing technique is used for slopes or excavations alongside highways, railway
lines etc.
4
Figure:- Soil Nailing In Railway Construction

5. CONSTRUCTION SEQUENCE
 Excavation of Slope
 Drilling Nail Holes
 Nail Installation and Grouting
 Construction of Temporary
Shotcrete Facing
 Construction of Subsequent Levels
 Construction of a Final, Permanent
Facing
5

6. APPLICATIONS
 Soil Nail Walls for Temporary and Permanent Cut Slopes
 Retaining Structure under Existing Bridge Abutments
 Repair and Reconstruction of Existing Retaining Structures
6

7. ADVANTAGES OF SOIL NAILING
• Economic Advantage
10% to 30% saving in cost when compared to an Anchored Diaphragm Wall.
• Simple & Light Construction Equipment
- Drilling Ring for nail installation
- Guns for shotcrete application
• Adaptability to Site Conditions
In heterogeneous ground where boulder or hard rocks may be encountered.
7

8. • Space
Soil nailing provides an obstruction free working space which can result in
considerable reduction in construction time for basement works and tunnel
construction.
• Structure Stability
Soil nailing use large number of nails, so failure of any one nail may not be
determine to the structure stability.
8

9. LIMITATION OF THE SYSTEM
 It requires cuts which can stand unsupported for depths of about 1 to 2 m at least for a
few hours prior to shotcreting & nailing. Otherwise a pretreatment such as grouting
may be necessary to stabilize the face.
 Soil nail walls are not well-suited where large amounts of groundwater seep into the
excavation because of the requirement to maintain a temporary unsupported
excavation face.
 Construction of soil nail walls requires specialized and experienced contractors.
9

10. COMPONENTS OF THE SYSTEM
Figure:- Component of Soil Nail Wall
10

11. SCOPE OF WORK
11
This dissertation is divided into two parts.
1) Experimental Work on Soil Nail Wall
The main aim of this study is to evaluate, how the soil nailed structure behaves at
different Inclination of Nailed Angle i.e. 10°, 15° and different L (length of nail )/H
(height of the wall) ratio i.e. 0.6, 0.7, 0.8 in comparison to Horizontal Nailing, i.e.
0° inclination. The Vertical Spacing (Sv) and Horizontal Spacing (Sh) is 10 cm
between two nails.
This experimental work has been carried out in a laboratory by using 12 mm dia.
Steel Bars (12 nos.) as nail on Cohesionless Soil (Poorly Graded Sand) in a Tank
(size: 100 × 50 × 80 cm) at a Relative Density of 50%. Wooden ply board (size: 1.9
× 50 × 80 cm) was used as a Rigid Facing. Maximum ultimate load has been found
out by applying the load up to the nailed wall failure.

12. 2) Analysis of Soil Nailed Wall
Analysis of soil nail wall using method proposed by Ramlingaraju (1996) and
Gupta (2003) are based on Moment Equilibrium Approach assuming the rupture
surface as log-spiral meeting the ground at 90°.
The calculation for the Factor of Safety has been shown using Excel tool.
12

13. LITERATURE REVIEW
ANALYTICAL STUDY
• The design of a soil nail wall should ensure that the system is safe against all of the
potential failure conditions are
External Failure Mode
Internal Failure Mode
Facing Failure Mode
13

14. • External Failure Modes
 Global Failure Mode
 Davis Deign Method
 German Design Method
 Kinematical Limit Analysis
 French Multicriteria Analysis
 Ramlingaraju and Gupta Design Method
 Sliding Failure Mode
 Bearing Failure Mode 14

15. THEORETICAL BACKGROUND
 The methods proposed by Ramligaraju (1996) and Gupta (2003) are based on
Moment Equilibrium Approach assuming the rupture surface as log-spiral
meeting the ground at 90°.
𝐅. 𝐎. 𝐒 =
𝐓𝐢 ∗ 𝒍𝒊 + 𝐓𝐜𝐢 ∗ 𝒍𝒄𝒊 + 𝐌𝐜
𝐌𝐰𝐯 + 𝐌𝐰𝐡 + 𝐌𝐪𝐯 + 𝐌𝐪𝐡
15

16. 16
MWV = Moment of W (1 ± αv) about ‘O’
MWH = Moment of W*αh about ‘O’
Mqv = Moment of Q (1 ± αv) about ‘O’
Mqh = Moment of Q*αh about ‘O’
Mc = Moment of Cohesion about ‘O’
𝐅. 𝐎. 𝐒 =
𝐓𝐢 ∗ 𝐥𝐢 + 𝐓𝐜𝐢 ∗ 𝐥𝐜𝐢 + 𝐌𝐜
𝐌𝐰𝐯 + 𝐌𝐰𝐡 + 𝐌𝐪𝐯 + 𝐌𝐪𝐡

17. MWV = Moment of W (1 ± αv) about ‘O’
= 𝟏 ± 𝛂𝐯 𝐌𝟏 − 𝐌𝟐 − 𝐌𝟑
• M1 =
γ∗H3x3
3 1+9 tan2ϕ
e3α∗tan ϕ 3 ∗ tan ϕ ∗ cos ϕ + α + sin ϕ + α − 4 ∗ sin ϕ
δ = cot−1
1
sin ϕ
2 ∗ sin ϕ + α
sin α
− cos ϕ
• M2 =
1
12
∗ γ ∗ H3
x3
∗
sin3α
sin3 ϕ+α
∗
sin ϕ+δ ∗sin2ϕ∗cos ϕ+δ
sin2δ
• M3 =
1
2
∗ γ ∗ H3
cot ϕ + α x ∗ cos ϕ − y −
cot ϕ+α
3
MWH = Moment of W*αh about ‘O’
= 𝐌𝟒 − 𝐌𝟓 − 𝐌𝟔
• M4 =
γ∗H3x3∗αh
3 1+9 tan2ϕ
e3α∗tan ϕ 3 ∗ tan ϕ ∗ sin ϕ + α − cos ϕ + α − 3 ∗ tan ϕ ∗ sin ϕ + cos ϕ
• M5 =
1
12
∗ γ ∗ H3
x3
∗ αh ∗
sin3α
sin3 ϕ+α
∗
sin2 ϕ+δ ∗sin2ϕ
sin2δ
• M6 =
1
2
∗ γ ∗ H3 ∗ αh ∗ cot ϕ + α x ∗ sin ϕ +
1
3
17

18. Mqv = Moment of Q (1 ± αv) about ‘O’
= 𝐪 ∗ 𝐇𝟐 ∗ 𝐲 ∗ 𝐱 ∗ 𝐜𝐨𝐬 𝛟 −
𝐲
𝟐
∗ 𝟏 ± 𝛂𝐯
Mqh = Moment of Q*αh about ‘o’
= 𝐪 ∗ 𝐇𝟐 ∗ 𝐲 ∗ 𝐱 ∗ 𝐜𝐨𝐬 𝛟 −
𝐲
𝟐
∗ 𝟏 ± 𝛂𝐯
Mc = Moment of cohesion about ‘O’
=
𝐜 ∗ 𝐇𝟐 ∗ 𝐱𝟐
𝟐 ∗ 𝐭𝐚𝐧 𝛟
𝐞𝟐𝛂∗𝐭𝐚𝐧 𝛟 − 𝟏
18
x =
cosec ϕ + α
eα∗ tan ϕ −
sin ϕ
sin ϕ + α
y =
x ∗ sin α
sin ϕ + α
− cot ϕ + α
S = H ∗ y
𝑟 = 𝑟𝑜 ∗ 𝑒𝜀∗tan 𝜙

19. 19
𝐅. 𝐎. 𝐒 =
𝐓𝐢 ∗ 𝐥𝐢 + 𝐓𝐜𝐢 ∗ 𝐥𝐜𝐢 + 𝐌𝐜
𝐌𝐰𝐯 + 𝐌𝐰𝐡 + 𝐌𝐪𝐯 + 𝐌𝐪𝐡
𝐓𝐜𝐢 = Mobilized shear in ith nail.
It acts normal to the nail axis
𝐓𝐜𝐢 =
𝐂 ∗ 𝐌𝐩
𝐥𝐬𝐢 ∗ 𝐒𝐡
𝟏 −
𝐓𝐢
𝐓𝐩
Figure:- Forces acting on the Wedge ‘abd’
lci
α

20. 20
Figure:- Forces acting on the Wedge ‘abd’
𝑻𝒊 = Axial force in the ith nail at
the point of maximum bearing
moment
𝑻𝒊 = 𝐜 + 𝝈𝒏𝒊 𝒕𝒂𝒏 𝜹 𝒑𝒊𝑳𝒆𝒊 𝑺𝒉
𝐅. 𝐎. 𝐒 =
𝐓𝐢 ∗ 𝐥𝐢 + 𝐓𝐜𝐢 ∗ 𝐥𝐜𝐢 + 𝐌𝐜
𝐌𝐰𝐯 + 𝐌𝐰𝐡 + 𝐌𝐪𝐯 + 𝐌𝐪𝐡
li
α
𝐋𝒆𝒊 = Length of the ith nail
behind the failure surface

21. Ti = Axial force in the ith nail at the point of maximum bearing moment
Ti = c + σni ∗ tan δ ∗ pi ∗ Lei Sh = 𝑓1 ∗ pi ∗ lei Sh
Tp = Fully plastic axial force = 𝑓𝑦 ∗ 𝐴
A = c/s area of the nail =
𝜋
4
∗ 𝑑2
d = Diameter of nail
D = Grout hole diameter
𝜎𝑣 = γ * Depth of nail from top
𝜎𝑏 = σv ∗
1 + Ka
2
∗ tan
π
2
+
ϕ
4
∗ e
π
2+ϕ
Mp = Fully plastic moment capacity of nail (depends on nail yield stress and shape of nail).
𝑓𝑦 = Yield stress of nail.
𝑙𝑠𝑖 = Shear width =
8∗Mp
σb∗d
∗
d
D
∗ 1 −
Ti
Tp
C = 4 (Range 2 to 5)
21
𝐓𝐜𝐢 =
𝐂 ∗ 𝐌𝐩
𝒍𝒔𝒊 ∗ 𝐒𝐡
𝟏 −
𝐓𝐢
𝐓𝐩

22. Ti = Axial force in the ith nail at the point of maximum bearing moment
𝐓𝐢 = 𝐜 + 𝛔𝐧𝐢 ∗ 𝐭𝐚𝐧 𝛅 ∗ 𝐩𝐢 ∗ 𝐋𝐞𝐢 𝐒𝐡 = 𝒇𝟏 ∗ 𝐩𝐢 ∗ 𝐥𝐞𝐢 𝐒𝐡
c = Unit cohesion of the soil.
δ = Mobilized soil-nail interface friction angle =
2
3
ϕ
pi = Perimeter of the ith nail
Lei = Length of the ith nail behind the failure surface
f1 = limit bond stress of the soil nail interface. (ith obtained from pull-out test.)
ϴ = Nail inclination with horizontal
σni = Normal stress at the mid depth of ith nail in the length Lei.
σni =
σy ∗ cos2θ − σx ∗ sin2θ
cos 2θ + sin 2θ ∗ tan δ
σx = Ka ∗ σy, σy = γ ∗ i −
1
2
∗ Sv + q
Ka = Coefficient of active earth pressure
Sh =Horizontal spacing between two nails 22
𝐓𝐜𝐢 =
𝐂 ∗ 𝐌𝐩
𝐥𝐬𝐢 ∗ 𝐒𝐡
𝟏 −
𝐓𝐢
𝐓𝐩

23. Illustrative Example
RAMLINGARAJU AND GUPTA METHOD
• Height of wall, H = 8 m
• Φ = 30⁰
• c = 2 kN/m2
• ϒ = 18 kN/m3
• Surcharge, q = 8 kN/m2
• Nail inclination, θ = 10⁰
• fy =250000 kN/m2
• Length of Nail = 6.4 m
• Log-spiral failure angle, α = 35⁰
• Horizontal and Vertical Spacing, Sv & Sh = 0.7
• Number of nail required, n = 11
23

24. x =
cosec ϕ + α
eα∗ tan ϕ −
sin ϕ
sin ϕ + α
= 1.26 m
y =
x ∗ sin α
sin ϕ + α
− cot ϕ + α = 0.32 m
𝐫𝐨 = 𝐇 ∗ 𝐱 = 10.08 m 𝐒 = 𝐇 ∗ 𝐲 = 2.56 m
Forces Acting on the Wedge
1) Weight W of the wedge ‘abd’ along with vertical seismic force, i.e. W (1 ± 𝛂𝐯)
W = Wt. of ‘Obd’ – Wt. of ‘Oed’ – Wt. ‘aed’
Moment M1 of Wt. W1 of ‘Obd’ about “O”.
M1 =
γ ∗ H3
x3
3 1 + 9 tan2ϕ
e3α∗tan ϕ 3 ∗ tan ϕ ∗ cos ϕ + α + sin ϕ + α − 4 ∗ sin ϕ
= 4039.21 kN m/m
Moment M2 of Wt. W2 of ‘Oed’ about “O”.
δ = cot−1
1
sin ϕ
2 ∗ sin ϕ + α
sin α
− cos ϕ = 12.39⁰ 24

25. M2 =
1
12
∗ γ ∗ H3
x3
∗
sin3
α
sin3 ϕ + α
∗
sin ϕ + δ ∗ sin2
ϕ ∗ cos ϕ + δ
sin2δ
= 1048.014 kN m/m
Moment M3 of Wt. W3 of ‘aed’ about “O”.
M3 =
1
2
∗ γ ∗ H3
cot ϕ + α x ∗ cos ϕ − y −
cot ϕ + α
3
= 1320.61 kN m/m
𝐌𝐰𝐯 = 𝟏 ± 𝛂𝐯 𝐌𝟏 − 𝐌𝟐 − 𝐌𝟑 = 1754.115 kN m/m
2) Moment of W * 𝛂𝐡 about “O”.
Moment M4 of W1 * 𝛼h about “O”.
M4 =
γ ∗ H3x3 ∗ αh
3 1 + 9 tan2ϕ
e3α∗tan ϕ
3 ∗ tan ϕ ∗ sin ϕ + α − cos ϕ + α − (3 ∗ tan ϕ ∗ sin ϕ) + cos ϕ
= 496.22 kN m/m
Moment M5 of W2 * 𝜶𝒉 about “O”.
M5 =
1
12
∗ γ ∗ H3x3 ∗ αh ∗
sin3α
sin3 ϕ + α
∗
sin2 ϕ + δ ∗ sin2ϕ
sin2δ
= 95.51 kN m/m
Moment M6 of W3 * αh about “O”.
M6 =
1
2
∗ γ ∗ H3 ∗ αh ∗ cot ϕ + α x ∗ sin ϕ +
1
3
= 206.143 kN m/m 25

26. 𝐌𝐰𝐡 = 𝐌𝟒 − 𝐌𝟓 − 𝐌𝟔 = 194.567 kN m/m
3) Moment at Q about “O”.
Moment of Q * (1 ± 𝜶𝒗) about “O”.
𝐌𝐪𝐯 = 𝐪 ∗ 𝐇𝟐 ∗ 𝐲 ∗ 𝐱 ∗ 𝐜𝐨𝐬 𝛟 −
𝐲
𝟐
∗ 𝟏 ± 𝛂𝐯 = 159.98 kN m/m
Moment of Q * αh about “O”.
𝐌𝐪𝐡 = 𝐪 ∗ 𝐇𝟐 ∗ 𝛂𝐡 ∗ 𝐱 ∗ 𝐲 ∗ 𝐬𝐢𝐧 𝛟 = 10.32 kN m/m
4) Moment of Cohesion force c about “O”.
𝐌𝐜 =
𝐜 ∗ 𝐇𝟐
∗ 𝐱𝟐
𝟐 ∗ 𝐭𝐚𝐧 𝛟
𝐞𝟐𝛂∗𝐭𝐚𝐧 𝛟
− 𝟏 = 179.85 kN m/m
θ1 = cot−1
x
y
− cos ϕ
sin ϕ
= 9.25⁰
Oa = H ∗ y ∗
sin ϕ
sin θ1
= 7.96 m
m = cot−1
i − 1
2 ∗ Sv
H ∗ y ∗
sin ϕ
sin θ1
+ sin ϕ + θ1 cos ϕ + θ1 = 48.67⁰
26

27. Op = H ∗ y ∗
sin ϕ ∗ cos ϕ + θ1
sin θ1 ∗ sin m
= 8.21 m
𝑥 ∗
𝑒𝛼𝑖∗𝑡𝑎𝑛 𝜙
𝑐𝑜𝑠 𝑚 + 𝜃
= 𝑦 ∗
𝑠𝑖𝑛 𝜙 ∗ 𝑐𝑜𝑠 𝜙 + 𝜃1
𝑠𝑖𝑛 𝜃1 ∗ 𝑠𝑖𝑛 𝑚 ∗ 𝑠𝑖𝑛 𝜙 + 𝛼𝑖 − 𝜃
From trial and error, we get 𝛼𝑖 = 4⁰
pn =
Op ∗ cos ϕ + αi + m
sin ϕ + αi − θ
= 2.54 m
On = r0 ∗ eαi∗tan ϕ
= 10.49 m
Lei = L − pn = 3.86 m
𝐥𝐢 = 𝐎𝐧 ∗ 𝐬𝐢𝐧 𝛟 + 𝛂𝐢 − 𝛉 = 4.27 m
𝐥𝐜𝐢 = 𝐎𝐧 ∗ 𝐜𝐨𝐬 𝛟 = 9.1 m
5) Moment due to pull-out resistance of the length of nails behind the slip surface
σy = γ ∗ i − 1 2 ∗ Sv + q = 14.3 kN/m2
δ =
2
3
ϕ = 200
𝐾𝑎 =
1 − sin 𝜙
1 + sin 𝜙
= 0.33
27

28. σx = Ka ∗ σy = 4.72 kN/m2
σni =
σy ∗ cos2θ − σx ∗ sin2θ
cos 2θ + sin 2θ ∗ tan δ
= 12.89 kN/m2
pi = π ∗ d = 0.078 m
𝐓𝐢 = 𝐜 + 𝛔𝐧𝐢 ∗ 𝐭𝐚𝐧 𝛅 ∗ 𝐩𝐢 ∗ 𝐋𝐞𝐢 𝐒𝐡 = 2.76 kN
𝐌𝐩𝐢 = 𝐓𝐢 ∗ 𝐥𝐢 = 11.78 kN m/m
6) Moment of the mobilized shear acting in the nail normal to their axis
lsi =
8 ∗ Mp
σb ∗ d
∗
d
D
∗ 1 −
Ti
Tp
= 2.02 m
𝜎𝑏 = σv ∗
1 + Ka
2
∗ tan
π
2
+
ϕ
4
∗ e
π
2
+ϕ
= 49.65kN/𝑚2
Mp = 0.166 ∗ d3
∗ fy = 0.648 kN m
Tp = fy ∗ A = 122.72 kN 28

29. 𝐓𝐜𝐢 =
𝐂 ∗ 𝐌𝐩
𝐥𝐬𝐢 ∗ 𝐒𝐡
𝟏 −
𝐓𝐢
𝐓𝐩
= 1.79 kN
𝐌𝐬𝐜 = 𝐓𝐜𝐢 ∗ 𝐥𝐜𝐢 = 16.3 kN m/m
𝐅. 𝐎. 𝐒 =
𝐓𝐢 ∗ 𝐥𝐢 + 𝐓𝐜𝐢 ∗ 𝐥𝐜𝐢 + 𝐌𝐜
𝐌𝐰𝐯 + 𝐌𝐰𝐡 + 𝐌𝐪𝐯 + 𝐌𝐪𝐡
= 0.09812 𝑓𝑜𝑟 1𝑠𝑡 𝑛𝑎𝑖𝑙
29

30. 30
Excel Sheet
8 m α 35 degree
8 kN/m2
θ 10 degree
2 kN/m2
Sv 0.70 m
30 degree Sh 0.70 m
18 kN/m3
αh 0.10
αv 0.05
fy 250 N/mm2
25 mm n 11
25 mm i 1
6.40 m C 4
RAMLINGRAJU & GUPTA METHOD, Vertical Wall
Height of nailed wall, H
Ka
Length of Nail, L
0.33
Nail Diameter, d
Groute Diameter, D
INPUTS
Unit weight of soil, γ
δ 20
Surchrge, q
c
ɸ
Ramlingaraju and Gupta Method

31. M1 =
4278.27 kN-m
δ =
12.29 deg
M2 =
1095.21 kN-m
M3 =
1298.74 kN-m
Mwv =
1978.54 kN-m
{γ*H
3
*x
3
/[3(1+9*tan
2
ϕ)]} * [e
3*α*tanϕ
{3*tanϕ*cos(ϕ+α)+sin(ϕ+α)} - 4*sinϕ]
cot
-1
[(1/sinϕ)*(2*sin(ϕ+α)/sinα) - cosϕ]
1/12*γ*H
3
*x
3
*{sin
3
α/sin
3
(ϕ+α)}*{sin(ϕ+δ)*sin
2
ϕ*cos(ϕ+δ)/sin
2
δ}
1/2*γ*H
3
*cot(ϕ+α)*[x*cosϕ - y - (cot(ϕ+α)/3)]
(1±αv)*(M1 - M2 - M3)
M4 =
519.87 kN-m
M5 =
99.62 kN-m
M6 =
208.07 kN-m
Mwh =
212.18 kN-m
1/2*γ*H3
*αh*cot(ϕ+α)*[x*sinϕ + 1/3)]
M4 - M5 - M6
{γ*H
3
*x
3
*αh/[3(1+9*tan
2
ϕ)]}*[e
3*α*tanϕ
{3*tanϕ*sin(ϕ+α)-cos(ϕ+α)}-3*tanϕ*sinϕ+cosϕ]
1/12*γ*H
3
*x
3
*αh*{sin
3
α/sin
3
(ϕ+α)}*{sin
2
(ϕ+δ)*sin
2
ϕ/sin
2
δ}
31

32. 32
Mqv = Mqh =
169.96 kN-m 11.05 kN-m
Mc =
183.19 kN-m
(c*H2
*x2
/2*tanϕ)*(e2*α*tanϕ
- 1)
q*H2
*y*[x*cosϕ - y/2]*[1±αv] q*H2
*αh*x*y*sinϕ
li = lci =
4.30 m 9.16 m
Ti = Tp = fy*A
2.77 kN 122.5 kN
Tci =
1.80 kN
Mpi = Msc =
11.91 kN-m 16.49 kN-m
{(C*Mp)/(lsi*Sh)}*[1-(Ti/Tp)]
Ti * li Tci * lci
On*sin(ϕ+αi-θ)
(c + σni*tanδ)*Pi*lei / Sh
On*cosϕ

33. 33
n = 11 αi li lci Ti Tci Mpi Msc
1 4.00 4.30 9.16 2.77 1.80 11.91 16.49
2 7.20 4.99 9.46 4.57 2.45 22.8 23.18
3 10.20 5.66 9.75 6.43 2.93 36.39 28.57
4 13.20 6.36 10.05 8.53 3.36 54.25 33.77
5 16.10 7.04 10.35 10.82 3.68 76.17 38.09
6 19.00 7.74 10.65 13.45 3.98 104.1 42.39
7 21.80 8.44 10.96 16.36 4.23 138.08 46.36
8 24.50 9.12 11.27 19.59 4.46 178.66 50.26
9 27.20 9.80 11.57 23.29 4.63 228.24 53.57
10 29.90 10.50 11.89 27.49 4.80 288.65 57.07
11 32.50 11.19 12.21 32.12 4.89 359.42 59.71
1498.67 449.46
i =
0.9
𝐅𝐎S =
𝐓𝐢𝐥𝐢
𝐧
𝐢 𝟏 + 𝐓𝐜𝐢𝐥𝐜𝐢 + 𝐌𝐜
𝐧
𝐢 𝟏
𝒗+ 𝒉+ 𝒗+ 𝒉
=

34. 34
6 m α
8 kN/m
2
i
2 kN/m2
αh
38 degree αv
18 kN/m3
λ (+) ve sign (-) ve sign
250 kN/m2
5.44 6.01
Kad 0.286 0.265
Max. Kad
250000 kN/m
2
Bearing Capacity of soil
Static Case Seismic Case
Height of nailed wall, H 0
Surchrge, q 0
c 0.10
ɸ 0.05
Unit weight of soil, γ
δ
Ka 0.286
fy
25.34
0.217
ANALYSIS OF SOIL NAIL WALL
Swami Saran

35. Paϒ = Paϒi =
70.31 kN/m 22.36 kN/m
Paq = Paqi =
10.42 kN/m 3.32 kN/m
Pac = PTs =
11.18 kN/m 25.68 kN/m
PTst =
69.55 kN/m
Maϒ = Maϒi =
140.62 kN-m/m 67.08 kN-m/m
Maq = Maqi =
31.26 kN-m/m 13.28 kN-m/m
Mac = MTs =
33.54 kN-m/m 80.36 kN-m/m
MTst =
138.34 kN-m/m
(Kad - Ka) * q * H
Paϒ + Paq - Pac
Paϒi + Paqi
2*c*Ka
1/2
*H
Total Earth Pressure & Moments Dynamic Increment & Moment
Paϒ * H/3
Maϒ + Maq - Mac
Paϒi * H/2
Maϒi + Maqi
Paq * H/2 (2/3) * Paqi * H
0.5 * Ka * ϒ * H2
0.5 * (Kad - Ka) * ϒ * H2
Ka * q * H
c*Ka
1/2
*H2
25 mm μ 0.5
4.8 m L/H 0.8
Ww = ϒ * H * L Wswh = Ww * αh Wswv = ± Ww * αv
kN/m 518.40 51.84 25.92
Mw = Ww * L/2 Mswh = Ww * H/2 *αh Mswv = ± Ww * L/2 * αv
kN-m/m 1244.16 155.52 62.21
Q = q* L Psqh = q * L * αh Psqv = ± q * L * αv
kN/m 38.40 3.84 1.92
Mq = q * L2
/2 Msqh = Q * H * αh Msqv = Q * L/2 * αv
kN-m/m 92.16 23.04 4.61
Diameter of nails, d
Static Case
Force & Moments related Nail Soil Excavation
Seismic Case
Assume
Length of nails, L
35

36. 36
External Stability
Sliding
Static Case Seismic Case
Fs =μ (Ww + Q)/PTst Fs =
μ (Ww + Q)*(1 ± αv)/
(PTst + Paϒi + Paqi + (Ww + Q)*αh
4.00 > 2, Safe 1.94> 1.5, Safe
Overturning
Static Case Seismic Case
Fo =(Mw + Mq) / MTst Fo =
(Mw + Mq + Mswv + Msqv)/
(MTst + Maϒi + Maqi + Mswh +Msqh)
9.66 > 2, Safe 3.54> 1.5, Safe
Tilting / Bearing Failure
Static Case Seismic Case SBC (kN/m2
)=250
σmax = [(Ww + Q)/L] + (MTst * 6/L2
) σmax =
[(Ww+Q)*(1±αv)/L] +
((MTst + MTs + Mswh + Msqh) * 6/L2
)
152.03< SBC, Safe 225.26< SBC, Safe
σmin = [(Ww + Q)/L] - (MTst * 6/L2
) σmin =
[(Ww+Q)*(1±αv)/L] -
(MTst + MTs + Mswh + Msqh) * 6/L2
)
79.98> 0, Safe 18.35> 0, Safe

37. 37
hi 6 m
σvi = σvi =
152.03 kN/m2
248.21 kN/m2
M1 = M1 =
138.33 kN-m/m 226.52 kN-m/m
Assume Maϒi =
ϒ(Kad-Ka) hi
3
(2H-hi) / 4H
Maqi =
q(Kad-Ka) hi
2
(3H-hi) / 3H
Fnail = 67.07 kN-m/m 13.25
Fmax = M3 =
31.13 * Sv
2
485.4 kN-m/m
Tstress = Fmax =
137500 kN/m
2
70.99 * Sv
2
Tforce = Tforce =
67.496 kN 84.369 kN
Fmax = Tforce Fmax = Tforce
Sv = 1.5 m Sv = 1.1 m
(Ka * σvi - 2c*Ka
1/2
) * Sv * Sh
M1 + Maϒi + Maqi + αh(ϒ*L*hi
2
/2) + αh*q*L*hi
(ϒi * hi + q) ± αv*(ϒi * hi + q )+ M3 * 6/L
2
In Limiting Case In Limiting Case
(ϒ * hi + q) + M1 * 6/L
2
1/6*ϒ*Ka*hi
3
+ (Ka*q*hi
2
/2)
- (c*Ka
1/2
*hi
2
)
1/6 * ϒ * Kad *hi
3
+ (Kad *q * hi
2
/ 2)
0.55 * fy
Tstress * π/4 * d
2
(Ka * σvi - 2c*Ka
1/2
) * Sv
2
Take hi = H
Sv = Sh
1.25 * Tstress * π/4 * d
2
Kad * σvi * Sv
2
Tension Failure
Static Case Seismic Case
Internal Stability

38. Figure : (a) The Cross-Section of the Soil Nailed Wall with a Planar
Failure Surface
(b) The Most Efficient Installation Angle of a Nail
1. The Effect of Upward Nail Inclination to the Stability of Soil Nailed Structure
(2004)
By: Erol Güler and Cemal F. Bozkurt
38
Previous work on Topic
(a) (b)

39. 𝐹𝑂𝑆 =
𝑅𝑒𝑠𝑖𝑠𝑡𝑖𝑛𝑔 𝐹𝑜𝑟𝑐𝑒
𝐷𝑟𝑖𝑣𝑖𝑛𝑔 𝐹𝑜𝑟𝑐𝑒
Downward Nailing, FOS =
c∗L + w∗cos θ + T∗sin β ∗tan ϕ
w∗sin θ − T∗cos β
Upward Nailing, FOS =
c∗
H
sin θ
+
H2
2∗tan θ
∗γ∗cos θ∗tan ϕ + T∗sin β∗tan ϕ
H2
2∗tan θ
∗sin θ − T∗cos β
Where,
L = Length of the failure surface,
w = The weight of the soil portion in the left part of the failure surface,
c = Cohesion of the soil,
Φ = Internal friction angle of the soil,
T = Mobilized tension on the nail,
β = The angle of the nail with the failure surface,
H = Height of the wall,
ϒ = Unit weight of the soil.
39

40. c
(kN/m2)
ϕ
( ° )
Factor of Safety
(F.S.1) for nails
inclined 15° below
horizontal
Factor of Safety
(F.S.2) for nails
inclined 5° above
horizontal
%difference
𝐅. 𝐒. 𝟐 − 𝐅. 𝐒. 𝟏
𝐅. 𝐒. 𝟏
5 20 0.68 0.77 13%
5 30 0.94 1.07 13%
100 10 4.99 5.66 13%
150 10 7.41 8.41 13%
40
Table: Comparison of Factor of Safeties for soil nailed walls
with different nail inclinations (ϒsoil = 19 kN/m3)

41. Depth of excavation (m) Nails inclined (-5°) Nails inclined (15°)
0.0 0 0
2.4 5 5
3.4 5 10
4.4 5 15
5.4 10 20
6.4 15 25
41
Table: Total horizontal lateral displacement at the
top of the wall (δh in mm)

42. 2. An Experimental Study on Horizontal and Inclined Soil Nails in Sand (2013)
By: Dr. A. K. Verma, Dr. D. R. Bhatt and Vaibhav Javia
Experimental Setup
Tank:-
Size: 100 cm X 50 cm X 80 cm (One side wall and both end walls - 5 mm
thick mild steel, remaining side of the -10 mm thick Perspex sheet )
 Materials
Soil:-
Poorly graded sand (SP)
Nails:-
Steel bars - 12 mm diameter
42

43. Figure(a): Horizontal Nailing
Figure(b): Inclined Nailing
(a)
(b)
43

44. The equation of factor of safety,
𝐹𝑂𝑆 =
𝑈𝑙𝑡𝑖𝑚𝑎𝑡𝑒 𝐿𝑜𝑎𝑑 𝑖𝑛 𝑁𝑎𝑖𝑙𝑒𝑑 𝐶𝑜𝑛𝑑𝑖𝑡𝑖𝑜𝑛
𝑈𝑙𝑡𝑖𝑚𝑎𝑡𝑒 𝐿𝑜𝑎𝑑 𝑖𝑛 𝑉𝑒𝑟𝑔𝑖𝑛 𝐶𝑜𝑛𝑑𝑖𝑡𝑖𝑜𝑛
44
Figure:- Load v/s Settlement

45. EXPERIMENTAL STUDY
Identification of Soil
 Grain Size Analysis
 Specific Gravity Test
 Relative Density
 Direct Shear Test
Experimental Set-up for Laboratory Load Test
 Model Tank
 Model Wall Facing
 Preparation of Nails
 Testing Procedure
45

46.  Grain Size Analysis:
46
From graph: D10 = 0.40, D30 = 0.65, D60 = 1.80
Cu = 4.50, CC = 0.094
Type of soil: Poorly Graded Sand (SP)
4.75
2.36
1.18
0.6
0.3
0.15
0.075
0
10
20
30
40
50
60
70
80
90
100
0.01 0.1 1 10
N
(%)
Sieve Dia. (mm)

47. Sr. No. Properties of Sand Tested Values
1 Coefficient of Uniformity, Cu 4.50
2 Coefficient of Curvature, Cc 0.094
3 Type of Soil Poorly graded sand
4 ρmax 1.89 gm/cm3
5 ρmin 1.49 gm/cm3
6 Specific Gravity, G 2.63
7 Angle of internal friction, ϕ 38.57°
8 Relative Density, Rd 50 %
9 Field Density, ρd 1.67 gm/cm3
47

48. Experimental Set-up For Laboratory Load Test
Model Tank:
• Experiments on model wall were conducted in a rigid steel tank directly rested on
base frame of steel channels which in turn rested on cement concrete floor.
• Test tank size was 100 cm × 50 cm × 80 cm.
• Three sides of tank was built by 5 mm thick mild steel. The remaining fourth side of
the tank was built by 10 mm thick Perspex sheet.
• The total inside length of the tank behind the facing was 60 cm.
• Vertical load is applied gradually by hydraulic pressure.
48

49. 49
Figure:- Model Tank and Nail Arrangement

50. Figure :- Play Board
 Preparation of Nails:
• Steel bars is used Fe 415 and diameter of 12 mm.
• Steel bars was cut according to design (L/H) and then threading is done on the end
part of the nails and then front part is grind for easy penetration in sand.
• The threading was to facilitate to tighten the nuts on it (nail) to fit with ply board.
Steel bars used were Fe 415 and diameter of 12 mm.
 Model Wall Facing:
• A 19 mm thick ply board (80 cm high and 48 cm wide) is used as a pre-placed
continuous facing. Circular holes of diameter 16 mm was made on pre-placed
continuous facing at the horizontal and vertical spacing.
50
Figure :- Nails

51. Loading Frame
51
Dial Gauge
Proving Ring
Steel Plate
Ply Board
Setup for Load Test

52. Testing procedure:-
• Ply board facing was placed vertically across the tank at a distance of 60 cm from
rear end of tank.
• Initially load test was perform on plate size (48 cm × 8 cm × 2 cm) without nailing
condition.
• Initially sand was filled on both sides of facing with same soil and density. Then
other side of tank will empty step by step as nailing was done so it could be similar
to actual practice.
• Plate was place at 20 cm from the inner side of facing. Two dial gauges will fit
diagonally on strip footing to get average deflection.
• The load was apply gradually by means of loading frame. The load was measure
by proving ring.
• Ultimate load have been found out using double tangent method.
52

53. Table: List of Experimental Trials
53
Trial
No.
Length of
nail
L (cm)
Height of
sand fill
H (cm)
L/H
Horizontal
Spacing
Sh (cm)
Vertical
Spacing
Sv (cm)
Nail
Pattern
Nail
Angle
θ (deg.)
1 24 40 0.6 10 10 3 x 4 0°
2 24 40 0.6 10 10 3 x 4 10°
3 24 40 0.6 10 10 3 x 4 15°
4 28 40 0.7 10 10 3 x 4 0°
5 28 40 0.7 10 10 3 x 4 10°
6 28 40 0.7 10 10 3 x 4 15°
7 32 40 0.8 10 10 3 x 4 0°
8 32 40 0.8 10 10 3 x 4 10°
9 32 40 0.8 10 10 3 x 4 15°

54. RESULTS
54
L/H
θ⁰
Inclination
Ultimate Load
(N)
Settlement
(mm)
0.8
0 1700 1.8
10 1900 1.8
15 1300 2
0.7
0 1200 3
10 1350 2.4
15 1150 3.5
0.6
0 700 1.8
10 1100 1.8
15 650 2.2

55. 1. Effect of L/H ratio
 From the figure shows that the value of Ultimate Load carrying capacity is
maximum for L/H = 0.8 in sand for driven nails.
55
600
1100
1600
2100
0.6 0.7 0.8
Ultimate
Load
(N)
L/H Ratio
0⁰ 10⁰ 15⁰
Fig.: L/H ratio v/s Ultimate Load Curve for Different Nail Inclination

56. 2. Effect of Nail Inclination
 From figure shows that the value of ultimate load is maximum for 10⁰ inclination
and it is reduced for the 15⁰ inclination of nail in comparison to horizontal nail.
56
600
1100
1600
2100
0 5 10 15
Ultimate
Load
(N)
Nail Inclination, θ ( ⁰ )
0.8 0.7 0.6
Fig.: Nail Inclination v/s Ultimate Load Curve for Different L/H ratio

57. 57

58. CONCLUSION
 From the experimental study load carrying capacity is maximum for L/H = 0.8.
 For the nail inclination of 10⁰ the load carrying capacity is maximum and settlement
reduces as compared to horizontal nails.
When nail inclination is 15⁰ the load carrying capacity and settlement reduction
reduce as compared to horizontal nails. So, inclined nail up to 10⁰ are more effective
as compared to horizontally inserted nails for same configuration.
58

59. REFERENCES
• Bowles J. E., “Foundation Analysis and Design”, 5th edition, Tata McGraw Hill Publishing
Company, 668.
• BS 8009: 1995 [Strengthened / reinforced soil and other fills]
• C. R. I. Clayton, R. I. Woods, A. J. Bond, J. Milititsky, “Earth Pressure & Earth Retaining
Structures”, 3rd Edition, CRC Press, 443.
• D. A. Bruce, “Soil Nailing: Application and Practice – Part 1 & 2”.
• Dhameliya K. B., (2014), “Analysis of Soil Nailed Surface”, M. E. Thesis, GTU.
• Dr. Verma A. K., Dr. Bhatt D. R. & Javia Vaibhav, (2013), “An Experimental Study on Horizontal
and Inclined Soil Nails in Sand”, Global Research Analysis, Volume 2, ISSN No 2277-8160.
• Dr. Verma A. K., Patel D. D., Joshi V. H. & Javia V. M., (2015), “A Study of Soil Nailing in Sand”,
Indian Geotechnical Journal, 33(3),71-72.
• Erol Güler and Cemal F. Bozkurt, (2004), “The Effect of Upward Nail Inclination to the Stability
of Soil Nailed Structure” Geo Trans, ASCE, 2213-2220.
59

60. • FHWA, (2003), “Geotechnical Engineering Circular No. 7: Soil Nail Walls”, Publication No.
FHWA-IF-03-017.
• FHWA, (2003), “Manual for design & Construction Monitoring of Soil Nail Walls”, Publication
No. FHWA-IF-03-017.
• G. L. Sivakumar Babu and Singh Vikas Pratap, “Stabilization of vertical cut using soil nailing”,
Plaxis Practice.
• IS 1888: 1982 [Bearing capacity of soil by plate load bearing test]
• IS 2720: Part 3: Sec 2: 1980 [Test for Soils - Part 3: Determination of Specific Gravity - Section 2:
Fine, Medium and Coarse Grained Soils]
• IS 2720: Part 4: 1985 [Methods of Test for Soils - Part 4: Grain Size Analysis]
• IS 2720: Part 13: 1986 [Methods of Test for Soils - Part 13: Direct Shear Test]
• IS 2720: Part 14: 1983 [Methods of Test for Soils - Part 14: Determination of Density Index
(Relative Density) of Cohesionless Soils]
• K. Premalatha, M. Muthu Kumar, D. Mohan Babu, (2009), “Analysis and Design of Nailed Soil
Wall - A Case Study”, IGC, Guntur, 574-577.
60

61. • K. Premalatha, M. Muthukumar and A. Amala Raju Arul, (2010), “Simplified Method of Design
of Nailed Soil wall”, GeoFlorida 2010: Advances in Analysis, Modeling & Design (GSP 199),
ASCE, 2271-2280.
• Mittal S., Gupta R. P. and Mittal N., (2005), “Housing Construction on Inclined Cuts”, Asian
Journal of Civil Engineering (Building and Housing) Vol. 6, No. 4, 331-346.
• Patra C. P. and Basudhar P. K., (2001), “Nailed Soil Structure: An Overview”, Indian Geotechnical
Journal, 31(4), 331-367.
• Shivakumar Babu, “Soil Reinforcement and Geosynthetics”, Universities Press, 118-134.
• Swami Saran, “Reinforced Soil and its Engineering Applications”, 2nd Edition, I. K. International
Publication House Pvt. Ltd., 261.
• T. Aishwarya and K. Ilamparuthi, (2013), “Study on Soil Nailing Based on Parametric Analysis”,
Indian Geotechnical Conference December 22-24, Roorkee.
• Wei Yiqing, (2013), “ Development of Equivalent Surcharge Loads for the Design of Soil Nailed
Segment of MSE/Soil Nail Hybrid Retaining Walls Based on Results from Full-Scale Wall
Instrumentation and Finite Element Analysis”, Texas Tech University.
• Wikipedia, the free encyclopedia http://en.wikipedia.org/wiki/soil_nailing.
61

62. 62