1. PILE FOUNDATION Session 17 – 26
Course : S0825/Foundation Engineering
Year : 2009
PILE FOUNDATION Session 17 – 26

2. PILE FOUNDATIONS SESSION 17 – 20 Topic: Types of pile foundation
Point bearing capacity of single pile
Friction bearing capacity of single pile
Allowable bearing capacity of single pile
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3. INTRODUCTION
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4. TYPES OF PILE FOUNDATION
STEEL PILE
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5. TYPES OF PILE FOUNDATION
CONCRETE PILE
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6. TYPES OF PILE FOUNDATION
CONCRETE PILE
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7. TYPES OF PILE FOUNDATION
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8. TYPES OF PILE FOUNDATION
WOODEN PILE
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9. TYPES OF PILE FOUNDATION
COMPOSITE PILE
COMBINATION OF:
STEEL AND CONCRETE
WOODEN AND CONCRETE
ETC
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10. PILE CATEGORIES END BEARING PILES
Classification of pile with respect to load transmission and functional behaviour:
END BEARING PILES
These piles transfer their load on to a firm stratum located at a considerable depth below the base of the structure and they derive most of their carrying capacity from the penetration resistance of the soil at the toe of the pile
FRICTION PILES
Carrying capacity is derived mainly from the adhesion or friction of the soil in contact with the shaft of the pile
COMPACTION PILES
These piles transmit most of their load to the soil through skin friction. This process of driving such piles close to each other in groups greatly reduces the porosity and compressibility of the soil within and around the groups.
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11. PILE CATEGORIES
END BEARING PILE
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12. PILE CATEGORIES
FRICTION PILE
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13. PILE CATEGORIES
Classification of pile with respect to effect on the soil
Driven Pile
Driven piles are considered to be displacement piles. In the process of driving the pile into the ground, soil is moved radially as the pile shaft enters the ground. There may also be a component of movement of the soil in the vertical direction.
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14. PILE CATEGORIES
Classification of pile with respect to effect on the soil
Bored Pile
Bored piles(Replacement piles) are generally considered to be non-displacement piles a void is formed by boring or excavation before piles is produced.
There are three non-displacement methods: bored cast- in - place piles, particularly pre-formed piles and grout or concrete intruded piles.
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15. PILE CATEGORIES
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16. DETERMINATION OF PILE LENGTH
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17. BEARING CAPACITY OF PILE
Two components of pile bearing capacity:
Point bearing capacity (QP)
Friction bearing capacity (QS)
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18. BEARING CAPACITY OF PILE
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19. POINT BEARING CAPACITY
For Shallow Foundation
- TERZAGHI
SQUARE FOUNDATION
qu = 1,3.c.Nc + q.Nq + 0,4..B.N
CIRCULAR FOUNDATION
qu = 1,3.c.Nc + q.Nq + 0,3..B.N
- GENERAL EQUATION
Where D is pile diameter, the 3rd term of equation is neglected due to its small contribution
Deep Foundation
qu = qP = c.Nc* + q.Nq* + .D.N*
qu = qP = c.Nc* + q’.Nq* ; QP = Ap .qp = Ap (c.Nc* + q’.Nq*)
Nc* & Nq* : bearing capacity factor by Meyerhof, Vesic and Janbu
Ap : section area of pile
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20. POINT BEARING CAPACITY MEYERHOF
PILE FOUNDATION AT UNIFORM SAND LAYER (c = 0)
QP = Ap .qP = Ap.q’.Nq*  Ap.ql
ql = 50 . Nq* . tan  (kN/m2)
Base on the value of N-SPT :
qP = 40NL/D  400N (kN/m2)
Where:
N = the average value of N-SPT near the pile point (about 10D above and 4D below the pile point)
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21. POINT BEARING CAPACITY MEYERHOF
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22. POINT BEARING CAPACITY MEYERHOF
PILE FOUNDATION AT MULTIPLE SAND LAYER (c = 0)
QP = Ap .qP
Where:
ql(l) : point bearing at loose sand layer (use loose sand parameter)
ql(d) : point bearing at dense sand layer (use dense sand parameter)
Lb = depth of penetration pile on dense sand layer
ql(l) = ql(d) = 50 . Nq* . tan  (kN/m2)
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23. POINT BEARING CAPACITY MEYERHOF
PILE FOUNDATION AT SATURATED CLAY LAYER (c  0)
QP = Ap (c.Nc* + q’.Nq*)
For saturated clay ( = 0), from the curve we get:
Nq* = 0.0
Nc* = 9.0
and
QP = 9 . cu . Ap
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24. POINT BEARING CAPACITY VESIC
BASE ON THEORY OF VOID/SPACE EXPANSION
PARAMETER DESIGN IS EFFECTIVE CONDITION
QP = Ap .qP = Ap (c.Nc* + o’.N*)
Where:
o’ = effective stress of soil at pile point
Ko = soil lateral coefficient at rest = 1 – sin 
Nc*, N* = bearing capacity factors
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25. POINT BEARING CAPACITY VESIC
According to Vesic’s theory
N* = f (Irr)
where
Irr = Reduced rigidity index for the soil
Ir = Rigidity index
Es = Modulus of elasticity of soil
s = Poisson’s ratio of soil
Gs = Shear modulus of soil
 = Average volumetric strain in the plastic zone below the pile point
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26. POINT BEARING CAPACITY VESIC
For condition of no volume change (dense sand or saturated clay):
 = 0  Ir = Irr
For undrained conditon,  = 0
The value of Ir could be estimated from laboratory tests i.e.: consolidation and triaxial
Initial estimation for several type of soil as follow:
Type of soil Ir
Sand
70 – 150
Silt and clay (drained)
50 – 100
Clay (undrained)
100 – 200
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27. POINT BEARING CAPACITY JANBU
QP = Ap (c.Nc* + q’.Nq*)
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28. POINT BEARING CAPACITY BORED PILE
QP =  . Ap . Nc . Cp
Where:
 = correction factor
= 0.8 for D ≤ 1m
= 0.75 for D > 1m
Ap = section area of pile
cp = undrained cohesion at pile point
Nc = bearing capacity factor (Nc = 9)
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29. FRICTION RESISTANCE Where: p = pile perimeter
L = incremental pile length over which p and f are taken constant
f = unit friction resistance at any depth z
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30. FRICTION RESISTANCE SAND
Where:
K = effective earth coefficient
= Ko = 1 – sin  (bored pile)
= Ko to 1.4Ko (low displacement driven pile)
= Ko to 1.8Ko (high displacement driven pile)
v’ = effective vertical stress at the depth under consideration
= soil-pile friction angle
= (0.5 – 0.8)
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31. FRICTION RESISTANCE CLAY
Three of the presently accepted procedures are:
 method
This method was proposed by Vijayvergiya and Focht (1972), based on the assumption that the displacement of soil caused by pile driving results in a passive lateral pressure at any depth.
 method (Tomlinson)
 method
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32. FRICTION RESISTANCE CLAY -  METHOD
Where:
v’= mean effective vertical stress
for the entire embedment length
cu = mean undrained shear strength ( = 0)
VALID ONLY FOR ONE LAYER OF HOMOGEN CLAY
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33. FRICTION RESISTANCE CLAY -  METHOD
FOR LAYERED SOIL
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34. FRICTION RESISTANCE CLAY -  METHOD
For cu  50 kN/m2
  = 1
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35. FRICTION RESISTANCE CLAY -  METHOD
Where:
v’= vertical effective stress
 = K.tanR
R = drained friction angle of remolded clay
K = earth pressure coefficient at rest
= 1 – sin R (for normally consolidated clays)
= (1 – sin R) . OCR (for overconsolidated clays)
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36. FRICTION RESISTANCE BORED PILE
Where:
cu = mean undrained shear strength
p = pile perimeter
L = incremental pile length over which p is taken constant
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37. ULTIMATE AND ALLOWABLE BEARING CAPACITY
DRIVEN PILE
FS=
BORED PILE
D < 2 m and with expanded at pile point
no expanded at pile point
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38. EXAMPLE
A pile with 50 cm diameter is penetrated into clay soil as shown in the following figure:
GWL
5 m
20 m
NC clay
 = 18 kN/m3
cu = 30 kN/m2
R = 30o
OC clay (OCR = 2)
 = 19.6 kN/m3
cu = 100 kN/m2
Determine:
End bearing of pile
Friction resistance by , , and  methods
Allowable bearing capacity of pile (use FS = 4)
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39. PILE FOUNDATIONS SESSION 21 – 22 Topic: Settlement of Piles
Laterally Loaded Piles
Pull Out Resistance of Piles
Pile Driving Formula
Negative Skin Friction
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40. SETTLEMENT OF PILES S = S1 + S2 + S3 Where: S = total pile settlement
S1 = elastic settlement of pile
S2 = settlement of pile caused by the load at the pile tip
S3 = settlement of pile caused by the load transmitted along the pile shaft
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41. SETTLEMENT OF PILES Where:
Qwp = load carried at the pile point under working load condition
Qws = load carried by frictional (skin) resistance under working load condition
Ap = area of pile cross section
Ep = modulus of elasticity of the pile material
L = length of pile
 = the magnitude which depend on the nature of unit friction (skin) resistance distribution along the pile shaft.
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42. SETTLEMENT OF PILES Where:
qwp = point load per unit area at the pile point = Qwp/Ap
D = width or diameter of pile
Es = modulus of elasticity of soil at or below the pile point
s = poisson’s ratio of soil
Iwp = influence factor
= r
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43. SETTLEMENT OF PILES Where: Qws = friction resistance of pile
L = embedment length of pile
p = perimeter of the pile
Iws = influence factor
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44. EXAMPLE
The allowable working load on a prestressed concrete pile 21 m long that has been driven into sand is 502 kN. The pile data are as follow:
- Diameter (D) = 356 mm
The area of cross section (Ap) = 1045 cm2
Perimeter (p) = m
Skin resistance carries 350 kN of the allowable load, and point bearing carries the rest. Use Ep = 21 x 106 kN/m2, Es = 25,000 kN/m2, s = 0.35 and  = 0.62)
Determine the settlement of the pile.
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45. EXAMPLE S = S1 + S2 + S3 = 3.35 + 15.5 + 0.84 = 19.69 mm
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46. LATERALLY LOADED PILE
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47. LATERALLY LOADED PILE ELASTIC SOLUTION – EMBEDDED IN GRANULAR SOIL
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48. LATERALLY LOADED PILE
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49. LATERALLY LOADED PILE
For L/T  5
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50. LATERALLY LOADED PILE
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51. LATERALLY LOADED PILE
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52. LATERALLY LOADED PILE ELASTIC SOLUTION – EMBEDDED IN COHESIVE SOIL
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53. LATERALLY LOADED PILE
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54. LATERALLY LOADED PILE
ULTIMATE LOAD ANALYSIS – MEYERHOF – PILES IN SAND
ULTIMATE LOAD RESISTANCE (Qu(g))
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55. LATERALLY LOADED PILE
MAXIMUM MOMENT, Mmax DUE TO THE LATERAL LOAD Qu(g)
For long (flexible) piles in sand
MAXIMUM MOMENT, Mmax DUE TO THE LATERAL LOAD Qg
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56. LATERALLY LOADED PILE
ULTIMATE LOAD ANALYSIS – MEYERHOF – PILES IN CLAY
ULTIMATE LOAD RESISTANCE (Qu(g))
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57. LATERALLY LOADED PILE
MAXIMUM MOMENT, Mmax DUE TO THE LATERAL LOAD Qu(g)
For long (flexible) piles
MAXIMUM MOMENT, Mmax DUE TO THE LATERAL LOAD Qg
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58. PULL OUT RESISTANCE OF PILES
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59. PULL OUT RESISTANCE OF PILES
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60. PULL OUT RESISTANCE OF PILES
EXAMPLE:
A concrete pile 50 long is embedded in a saturated clay with cu = 850 lb/ft2. The pile is 12 in. x 12 in. in cross section. Use FS = 4 and determine the allowable pullout capacity of the pile
Solution
Given cu = 850 lb/ft2  kN/m2
’ = 0.9 – cu = 0.9 – ( )(40.73) = 0.645
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61. PULL OUT RESISTANCE OF PILES
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62. PULL OUT RESISTANCE OF PILES
For dry soils, the equation simplifies to
Determine the value of Ku and  from figure 9.36b and 9.36c.
Where Tun(all) = allowable uplift capacity and FS is Factor of Safety (a value of 2 – 3 is recommended)
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63. PULL OUT RESISTANCE OF PILES
EXAMPLE:
a precast concrete pile with a cross section 350 mm x 350 mm is embedded in sand. The length of pile is 15 m. Assume that sand = 15.8 kN/m3, sand = 35o, and the relative density of sand = 70%. Estimate the allowable pullout capacity of the pile (FS = 4)
Solution
From figure 9.36, for  = 35o and relative density = 70%
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64. PILE DRIVING FORMULA
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65. NEGATIVE SKIN FRICTION
Can occur under condition such as:
If a fill of clay soil is placed over a granular soil layer into which a pile is driven, the fill will gradually consolidate. This consolidation process will exert a downward drag force on the pile during a period of consolidation
If a fill of granular soil is placed over a layer of soft clay. It will induce the process of consolidation in the clay layer and thus exert a downward drag on the pile
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66. NEGATIVE SKIN FRICTION
CLAY FILL OVER GRANULAR SOIL
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67. NEGATIVE SKIN FRICTION
GRANULAR SOIL FILL OVER CLAY
THE UNIT NEGATIVE SKIN FRICTION AT ANY DEPTH FROM z = 0 TO z = L1
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68. NEGATIVE SKIN FRICTION
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69. GROUP PILES SESSION 23 – 24 Topic: Bearing Capacity of Group Piles
Group Efficiency
Piles in Rock
Consolidation settlement of Group Piles
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70. GROUP PILES Where: D = pile diameter
Lg = (n1 – 1)d + 2(D/2)
Bg = (n2 – 1)d + 2(D/2)
Where:
D = pile diameter
d = spacing of pile (center to center)
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71. GROUP PILES
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72. GROUP EFFICIENCY Where: = group efficiency
Qg(u) = ultimate load bearing capacity of the group pile
Qu = ultimate load bearing capacity of each pile without the group effect
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73. GROUP PILES IN SAND If  < 1  Qg(u) = .Qu If  1  Qg(u) = Qu
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74. GROUP PILES IN SAND
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75. GROUP PILES IN SAND
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76. GROUP PILES IN SAND
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77. GROUP PILES IN SAND Summary:
For driven group piles in sand with d  3D, Qu(g) may be taken to be Qu, which includes the frictional and the point bearing capacities of individual piles.
For bored group piles in sand at conventional spacings (d  3D), Qg(u) may be taken to be 2/3 to 3/4 times Qu (frictional and point bearing capacities of individual piles)
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78. GROUP PILES IN SATURATED CLAY
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79. GROUP PILES IN SATURATED CLAY
Calculation steps:
Determine Qu = n1.n2 (Qp + Qs)
where:
QP = 9 . cu . Ap (ultimate end bearing capacity of single pile)
QS = (.p.cu.L) (skin resistance of single pile)
Determine the ultimate capacity by assuming that the piles in the group act as a block with dimensional Lg x Bg x L as follow :
- end bearing capacity of the block
QP’ = Ap . qp = Ap . cu . Nc* with Ap = Lg . Bg
- Skin resistance of the block
QS’= (pg.cu.L) = 2.(Lg+Bg).cu.L
- Ultimate bearing capacity o pile group
Qu = QP’ + QS’
Qu = (Lg . Bg) . cu . Nc* + 2.(Lg+Bg).cu.L
Compare the values obtained in step 1 and 2  the lower of the two values is Qg(u)
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80. GROUP PILES IN SATURATED CLAY
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81. GROUP PILES IN SATURATED CLAY
Problem:
The section of a 3 x 4 group pile layered saturated clay. The piles are square in cross section (14 in. x 14 in.). The center to center spacing, d, of the piles is 35 in. Determine the allowable load bearing capacity of the pile group. USE FS = 4
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82. GROUP PILES IN SATURATED CLAY
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83. PILES IN ROCK
For point bearing piles resting on rock, most building codes specify that Qq(u) = Qu, provided that the minimum center to center spacing of piles is D mm. For H-Piles and piles with square cross sections, the magnitude of D is equal to the diagonal dimension of the pile cross section.
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84. CONSOLIDATION SETTLEMENT OF GROUP PILES
The Terzaghi formula is valid with some rules:
The consolidation settlement is occurred from the depth of 2/3 of pile length.
The stress increase caused at the middle of each soil layer by using 2:1 method
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85. CONSOLIDATION SETTLEMENT OF GROUP PILES
sat = 18,9 kN/m3
Cc = 0,2
eo = 0,7
sat = 19 kN/m3
Cc = 0,25
eo = 0,75
Problem:
A group pile with Lg = 3.3 m and Bg = 2.2 m as shown in the figure. Determine the consolidation settlement of the pile groups. All clays are normally consolidated.
sat = 18 kN/m3
Cc = 0,3
eo = 0,82
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86. ELASTIC SETTLEMENT OF GROUP PILES
VESIC
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87. ELASTIC SETTLEMENT OF GROUP PILES
MEYERHOF (Pile groups in sand and gravel)
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88. ELASTIC SETTLEMENT OF GROUP PILES
PILE GROUP SETTLEMENT RELATED TO THE CONE PENETRATION RESISTANCE
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89. UPLIFT CAPACITY OF GROUP PILES
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90. UPLIFT CAPACITY OF GROUP PILES
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91. PILE INSTALLATION AND LOADING TEST
SESSION 25 – 26
Topic:
Installation Method of Driven Pile
Installation Method of Bored Pile
Loading Test by Static Method
Loading Test by Dynamic Method
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92. INSTALLATION METHOD Pile Installation Equipment
The primary tools used in the actual driving
(installing) of piles are :
Impact Hammers,
Vibrator Driver / Extractors
Special Hydraulic Presses
Supporting Equipment – power sources,
hoisting & material handling equipment, etc.
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93. PILE INSTALLATION EQUIPMENTS
Types of Impact Hammers
Impact Hammers are identified by their method of operation or the motive force employed. They are generally identified as :
Drop Hammers
Air or Steam Hammers
Diesel Hammers
Hydraulic Impact Hammers
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94. PILE INSTALLATION EQUIPMENTS
Drop Hammers
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95. PILE INSTALLATION EQUIPMENTS
Air (or Steam) Hammers
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96. PILE INSTALLATION EQUIPMENTS
Air (or Steam) Hammers
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97. PILE INSTALLATION EQUIPMENTS
Diesel Hammers
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98. PILE INSTALLATION EQUIPMENTS
Diesel Hammers
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99. PILE INSTALLATION EQUIPMENTS
Hydraulic Impact Hammers
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100. PILE INSTALLATION EQUIPMENTS
Hydraulic Impact Hammers
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101. PILE INSTALLATION EQUIPMENTS
Vibro Driver/Extractors
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102. PILE INSTALLATION EQUIPMENTS
Vibro Driver/Extractors
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103. PILE INSTALLATION EQUIPMENTS
Hydraulic Press Installer
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104. PILE INSTALLATION EQUIPMENTS
Hydraulic Press Installer
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105. PILE INSTALLATION EQUIPMENTS
Land Based Rigs
Cantilever Fixed Lead
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(With Fixed Bottom Brace)
(With Spotter)

106. PILE INSTALLATION EQUIPMENTS
Land Based Rigs
Under slung Swinging Lead
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(With Fixed Bottom Brace)
(With stabbing points)

107. PILE INSTALLATION EQUIPMENTS
Land Based Rigs
European Style, Fixed Lead with Fixed Bottom Brace
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(Driving Aft Batter with Hydraulic Hammer)

108. PILE INSTALLATION EQUIPMENTS
Land Based Rigs
European Style, Fixed Lead on Crawler Lower
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109. DRIVEN PILE INSTALLATION
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110. BORED PILE INSTALLATION
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111. PILE QUALITY Two aspects of final quality of pile:
Structural integrity of pile.
Pile ability to support external load, consist of strength of structure element and relationship load-settlement between pile and soil support
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112. STATIC LOADING TEST TEST METHODS Use Static Load
The load is 200% of working load
Preparation before testing
Loading
Measurement of pile movement
Instrumentation
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113. STATIC LOADING TEST Loading Methods
Standard Method of Loading‑SML, Monotonic
Standard Method of Loading‑SML, cyclic
Quick Load Test (Quick ML)
Constant Rate of Penetration Method (CRP)
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Sumber : Manual Pondasi Tiang, GEC

114. Typical arrangements for axial compressive load test
Anchor Pile
Dead Load
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115. STATIC LOADING TEST
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116. STATIC LOADING TEST Test load arrangement using kentledge
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117. DYNAMIC LOADING TEST PDA (Pile Driving Analyzer)
DLT (Dynamic Load Test), TNO
Theory of wave propagation
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Sumber : Manual Pondasi Tiang, GEC

118. Strain gauge and accelerometer Interpretation of PDA result
PDA computer
Strain gauge and accelerometer
Interpretation of PDA result
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119. PULL OUT TESTS
Pullout load by using hydraulic jack between beam and reaction frame (ASTM D , 1989)
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Sumber : Manual Pondasi Tiang, GEC

120. PULL OUT TESTS
Pullout load by using hydraulic jack, one at each end of the beam (ASTM D , 1989)
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121. LATERAL LOADING TEST
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Sumber : Manual Pondasi Tiang, GEC

122. LATERAL LOADING TEST
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123. PILE INTEGRITY TEST
This test is needed to check the integrity of bored pile or driven pile.
Some methods generally adopted is by using the principle of wave propagation. The test is carried out by applying vibration and evaluating its reflection.
Through this test, the defect on pile will be able to detect.
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Sumber : Manual Pondasi Tiang, GEC