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104
10 1 0.1 0.01Particle Diameter, mm
0
20
40
60
80
100Pe
rcen
t Fin
er b
y W
eigh
t (%
)Ottawa Silica Sand (ASTM C-778)
Fig. 5.1. Grain size distribution of Ottawa sand
105
Fig. 5.2. Shear box of direct shear test device (after Wu, 1992)
106
15.00 15.50 16.00 16.50 17.00 17.50
Unit Weight, γ (kN/m3 )
25
30
35
40
45φ
(Deg
ree)
Air-Pluviation Sand
Compacted Sandφ = 6.43γ − 68.99
φ = 7.25γ − 79.51
Fig. 5.3. Relationship between unit weight γ and internal friction angle (after Chang, 2000)
107
(a)
(b)
Fig. 5.4. Soil hopper
Unit:mm
500
800
430
120
Slot Control HandleSlot Opening
Slot Opening Slot Control Handle
108
Fig. 5.5 Pluviation of the Ottawa sand into soil bin
Sand Hopper
SPT
Model Wall
Raining of Ottawa Sand
Steel Interface
Plate
109
1500
Unit: mm
SPT2
SPT1
Lift 1 SPT3
SPT4
Lift 2
SPT7
SPT5
SPT6
SPT8
SPT9
Ottawa SandLift 3
SPT10
SPT11
Lift 4
SPT13
SPT12
SPT14
150035Model Wall
Lift 5 SPT15
45
.
Side-view
300
300.
Fig. 5.6. Backfill compacted with square compactor in 5 lifts
α
110
1500
Unit: mm
Lift 2 SPT2
Lift 1 SPT1
Lift 3
Lift 4
SPT3
SPT4
Lift 7 SPT7
Lift 5
Lift 6
SPT5
SPT6
Lift 8
Lift 9
SPT8
SPT9
Ottawa Sand Lift 10
Lift 11
SPT10
SPT11
Lift 13
Lift 12
Lift 14
SPT13
SPT12
SPT14
150035Model Wall
Lift 15 SPT15
45
Side-view
100
100
Fig. 5.7. Backfill compacted with strip compactor in 15 lifts
α
111
6
5
4
3
2 .250
Lane 1
Orrawa Sand
Soil Compactor
Model Wall Soil Pressure Transducer
Steel Column
Top-view
Fig. 5.8. Backfill compacted with square compactor in 6 lanes
112
11
13
1514
12
9
7
5
3
1
10
8
6
4
2
Soil Compactor
.
Lnae
100
Ottawa Sand
Model Wall Soil PressureTransducer
Steel Column
Top-view
Fig. 5.9. Backfill compacted with strip compactor in 15 lances
113
Fig. 5.10. Soil-density control cup
unit : mm
Top-view
Side-view
Acrylic Tube
Acrylic Base Plate30
5
43
3.5
70
70
70
43
50
114
Fig. 5.11. Soil-density cup
115
Density cups
1990
Unit : mm
Stee
l col
umn
WallModel
1500
45 1500
Steel base plate
Elevation
35
Ottawa Sand
Walkway
215
Fig. 5.12. Soil density cups buried at the different elevations
116
Soil PressureTransducer
Steel Base Plate
Top-viewSteel Beam
Model Wall
Steel Column
Density Cup
SideWall Sidewall
Ottawa Sand
Fig. 5.13. Locations of soil density cups at same elevation
117
0 20 40 60 80 100Relative Density, Dr(%)
0
0.3
0.6
0.9
1.2
1.5E
leva
tion
(m)
This StudyChen (2002)
Air-PluviationOttawa SandDrop Height = 1.5 mSlot opening = 18 mm
Drop Height = 1.0 mSlot Opening = 15 mm
Fig. 5.14. Distribution of soil density for loose sand
118
(a) Compaction at H = 1.2 m (α = 60o)
(b) Compaction at H = 1.2 m (α = 60o)
Fig. 5.15. Compaction of backfill with square compactor
Vibratory Compactor Steel Interface Plate
Ottawa Sand
Model Wall
SPT
Ottawa Sand Vibratory Compactor
119
0 20 40 60 80 100Relative Density, Dr (%)
0
0.3
0.6
0.9
1.2
1.5E
leva
tion
(m)
This StudyChen, 2003
Compacted SandSquare Compactor Lift = 0.3 m
Fig. 5.16. Distribution of soil density compacted with square compactor
120
(a) Compaction at H = 1.1 m (α = 70o)
(b) Compaction at H = 1.1 m (α = 70o)
Fig. 5.17. Compaction of backfill with strip compactor
Acentric Motor
Steel Interface Plate
Vibratory Compactor
Model Wall
SPT
Ottawa Sand
Steel Interface Plate
Vibratory Compactor
Plastic Sheets
121
0 20 40 60 80 100Relative Density, Dr (%)
0
0.3
0.6
0.9
1.2
1.5E
leva
tion
(m)
Compacted SandStrip Compactor Lift = 0.5 m
0.1 m
Air-PluviatedLoose Sand(Dr = 31~39%)
Dense Sand
Fig. 5.18. Distribution of soil density compacted with strip compactor (Lift = 0.5 m)
122
0 20 40 60 80 100Relative Density, Dr (%)
0
0.3
0.6
0.9
1.2
1.5El
evat
ion
(m)
Compacted SandStrip CompactorLift = 0.1 m
Dr = 70%Air-PluviatedLoose Sand(Dr = 31~39%)
Dense Sand
Fig. 5.19. Distribution of soil density compacted with strip compactor (Lift = 0.1 m)
123
0 20 40 60 80 100Relative Density, Dr (%)
0
0.3
0.6
0.9
1.2
1.5E
leva
tion
(m) Strip Compactor
Square Compactor
Compacted Sand
Lift = 0.1 m(This Study)
Lift = 0.3 m (Chen, 2002)
Fig. 5.20. Comparison of density distribution compacted with strip and square compactors
124
Fig. 5.21. Relative density vs. Depth relation for vibratory
roller compaction (after D’Appolonia et al., 1969)
125
Fig. 5.22. Lubrication layer hung on the side wall
Lubrication Layer (Plastic Sheets)
Model Wall
126
Fig. 5.23. Schematic diagram of sliding block test (after Fang et al., 2004)
δ
Lubrication Layer
Handle
Standard Weight
Soil Box
Uplift Rod
Worm Gear
Horizontal LineN
T
F
27 mm
60 mm
Acrylic Plate
20 mm10 mm
Steel Plate
900 mm
600 mm
127
Fig. 5.24. Sliding block test apparatus (after Fang et al., 2004)
Standard weight↓
↙ Sliding plate↙ Soil boxPlastic sheet ↘
←
Ball bearing
Handle Worm gear
Uplift rod
128
1 10 100
Normal Stress, σ (kN/m2)
0
5
10
15
20
25Fr
ictio
n A
ngle
, δsw
(deg
ree)
Sliding Block TestPlastic-Sheet Method1 Thick + 2 Thin Sheeting
δsw = 7.5o
Fig. 5.25. Variation of interface angle with normal stress (after Fang et al., 2004)
129
(a)
(b) Smooth Steel Plate
Fig.5.26 Direct Shear Test Arrangement to Determinate Wall Friction Angle
Smooth Steel Plate
Unit : mm
130
15.5 15.75 16 16.25 16.5 16.75 17 17.25Unit Weight , γ (kN/m3)
8
9
10
11
12
13
14
15δ w
(deg
ree)
Test Data (air-pluviation)δw = 3.41γ - 43.69Test Data (compaction)δw = 3.08γ - 37.54
σn = 79.8 kN/m2Ottawa Sand
Fig. 5.27. Relationship between unit weight γand
wall friction angle δw (after Ho, 1999)
131
120
20
63
Dry Ottawa Sand
Steel Plate
Safety-Walk
N
5
Upper Shear Box
Unit : mm (a)
80
5
120
15
20
80
80
Unit : mm
Safety-Walk
(b)
Fig. 5.28. Direct shear test arrangement to determine interface friction angle
Anti-Slip MaterialSafety-Walk
132
15 16 17 18 19Unit Weight, γ (kN/m3)
10
15
20
25
30
35δ i
(deg
ree)
Air-Pluviation Snad
Compacted Sand
δi = 2.7 γ - 21.39
δi = 1.97 γ - 8.9
Ottawa Sandσn = 4.60 kN/m2
Fig. 5.29 Relationship between unit weight γ and interface plate friction
angle δi
133
15 15.5 16 16.5 17 17.5 18 18.5 19Unit Weight , γ (kN/m3)
0
5
10
15
20
25
30
35
40
45
Fric
tion
Ang
le (d
egre
e)
Internal Friction Angle, φ
φ = 6.43γ − 68.99 (Chang, 2000)
Steel-Plate Friction Angle, δi
δi = 2.7γ − 21.39
Model Wall Friction Angle, δw
δ w = 3.41γ − 43.69 (Ηο, 1999)
Sidewall Friction Angle, δswδsw = 7.5o (Fang et al., 2004)
Ottawa Sand(Air-Pluviated)
(a) Air-Pluviated Sand
(b) Compacted Sand
Fig. 5.30. Relationship between unit weight γ and
different friction angles
15 15.5 16 16.5 17 17.5 18 18.5 19Unit Weight , γ (kN/m3)
0
5
10
15
20
25
30
35
40
45
Fric
tion
Ang
le (d
egre
e)
Internal Frict
ion Angle, φ
φ = 7.25γ − 79.51 (C
hang, 2000)
Steel-Plate Interface Friction Angle, δi
δi = 1.97γ − 8.9
Model Wall Friction Angle, δw
δ w = 3.08γ − 37.54 (Ηο, 1999)
Sidewall Friction Angle, δswδsw = 7.5o (Fang et ai., 2004)
Ottawa Sand(Compacted)