of 89
Page 1
Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
Sample Design CalculationsFor Micropiles in Kenny
Hill Formation
Generalized Subsoil Profile
- Generally flat terrain
- Subsoil profile:0-3m, silty SAND, SPT=1- 53-6m, silty SAND, SPT= 15 - 50 6-20m, highly weathered sandstone
FOR INTERNAL USE ONLY
Mild Steel Capping PlateL = 350mmB = 350mmThickness = 10mm
Mild Steel Stiffeners
Pile Boring
API Pipe
Cementitious Grout
Safe Working Load
Thickness = 10mm
Diameter = 200mm
O.D. = 127.0mmThickness = 9.2mmfy (min) = 552 MpaGrade = N-80
W/c = 0.45Fcu = 25 Mpa
Pa = 80 tonnesLsocket = 20m
Schematic Detail
Soil becoming weathered rock
L = 20.0m
Page 2
Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
Subject : Micropile Design
1.0 Material Properties1.1 Basic Dimensions and Properties1.1.1 Micropile Diameter, D = 200mm1.1.2 Pile Composite Modulus Ep = 41 GPa1.1.3 Moment of Inertia, Ip = 7.85E+07 mm^4
1.2 Cementitious Grout1.2.1 Max. water/cement ratio = 0.451.2.2 Anti-shrink / Additives = Adogroud 100g 150kg bag1.2.3 Grout Area. Ac = 45686 mm"21.2.4 28 day Comp. Strength, Fcu' = 25 MPa1.2.5 Density = 2000 kg /M^31.2.6 Elastic Modulus. Ec = 28 GPa
1.3 API Pipe Reinforcement1.3.1 Source =1.3.2 Outer Diameter, OD = 127 mm1.3.3 Wall Thickness. t = 9.19 mm1.3.4 Inner Diameter. ID = 108.62 mm1.3.5 Cross Sectional Area, As = 3401 mm^21.3.6 API Specification = 5A-801.3.7 Grade Designation = N-801.3.8 Mm. Yield Strength, fy = 552 MPa1.3.9 Elastic Modulus. Es = 210 GPa
1.4 Compliance with British Standards Designed Req. Min. Source (Max)
1.4.1 Working Grout/API Pipe Bond (MPa) 0.8 12 BS81101.4.2 Grout Characteristic Strength, fcu (MPa) 25 20 BS80041.4.3 Cement content (kg/m"3) 400 00 BS80041.4.4 Grout working compressive stress,0.4fcu/FoS 0.2 x fcu 0.25 x fcu BS8004
1.5 Minimum Factors of Safety1.5.1 Against Structural Failure = 2.001.5.2 Against Buckling Failure = 1.601.5.3 Against Geotech. Failure = 2.00 Skin Friction1.5.4 Against Geotech. Failure = 2.50 End Bearing
2.0 Structural DesignAssuming that the applied vertical load is carried by the API Pipe alone.
2.1 Ultimate Load Capacity Pu = 0.87 x fy x As = 1633450 N = 1633.5 kN = 163.3 tonnes
Use the Factor of Safety prescribed in Section 1.5 on Plate 22.2 Allowable Load Capacity Pa = 82 tonnes
FOR INTERNAL USE ONLY
Page 3
Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
2.3 Design Safe Working LoadSWL = 80 tonnes
3.0 Geotechnical DesignRefer Piler Analysis for derivation of Geotechnical Safe Working Load -Appendix ......
3.1 Design Length3.1.1 Safe Working Load per Pile P = 800 kN3.1.2 Nominal Diameter D = 200 mm3.1.3 Embedment Ls = 20.0 m
3.2 Grout l API Pipe Bond3.2.1 Ultimate Grout Pipe - Bond Stress, t (u) = 2.0 MPa3.2.2 Factor of Safety = 2.53.2.3 Working Bond Stress, t (w) = 0.8 MPa3.2.4 Req'd API Pipe Embedment in Grout = 2.5 m
< 20.0 mTherefore, adopted socket length is OK
4.0 Buckling (Pile Slenderness) Analysis not appropriate for Kenny Hill Formation
4.1 Pile End Conditions (Unfilled Cavities)4.1.1 Pile Top (at Pilecap Level) = Fixed4.1.2 Pile Base (at Rock Head Level) = Fixed4.1.3 Ass. length in unfilled cavity L assumed = 1 m4.1.4 Effective Length - 0.7 x L L eff. = 0.7 m
4.2 Eucler's Buckling Load (Unfilled Cavities)4.2.1 Effective radius r =41.84.2.2 Euler Critical Load Pe =@pi^2 - Ep l(Lelr)^2 = 1428 kN
FOS available =9.78 OK
4.3 Elastic Buckling Load of Pile embedded in Overburden (ie Winkler Medium)4.3.1 Average SPT in Overburden soils,N = 504.3.2 Est. Und. Cohesion Overburden soils, Cu = 6 ' N kPa 300 kPa 4.3.3 Modulus of Horiz. Subgrade Reaction, kh'c = 67*Cu
20100 kPa = 20.1 MPa 4.3.4 Elastic Buckling Load, Pcr = 2 x @sgrt (Ep x Ip x kh x d)
= 16014 kN4.3.5 FOS available = 20.02 OK
5.0 Rate of Corrosion of Reinforcement5.1 Ex Oil Drill API Pipe Reinforcement5.1.1 Outer Diameter O.D. = 127.0 mm5.1.2 Wall Thickness t = 9.2 mm5.1.3 Internal Diameter I.D. = 108.6 mm5.1.4 Cross sectional Area As = 3401 mm^25.1.5 API Specification = 5A-805.1.6 Grade Designation = N-805.1.7 Min Yield Strength fy = 552 MPa
FOR INTERNAL USE ONLY
Page 4
Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
5.1.8 Elastic Modulus Es = 210 GPa5.1.9 Allowable Axial Working Stress (Clause 7.4.6.3.1 BS8004)
Fa = 50% of Yield Strength = 276 MPa
5.2 Design for allowable corrosion as for sheetpiles w/o grout/concrete protection
5.2.1 Allowable corrosion rate = 0.01 mm/year5.2.2 Max. pile axial load Pa = 800 kN5.2.3 Req'd Steel Area Asc = 2899 mm^25.2.4 Min. OD of API Pipe O.D. = 124.5 mm5.2.5 Allowable Corrosion Period Tc = 255 years
Summary
No additional reinforcement required, Tc > Design Life of 50 years.
6.0 Pilehead Capping DetailsSafe Working Load = 800 kN
6.1 Capping Plate Size6.1.1 Assume characteristic strength of pileca f cu = 25 MPa6.1.2 Permissible direct compressive stress fcu13.65 = 6.85 MPa6.1 3 Req'd bearing area of capping plate = 116800 mm^2
Adopt plate of dimmensions (mm) 350 x 350 OK
6.2 Thickness of Stiffners6.2.1 Allowable Axial Compressive Stress = 155 MPa
(Table 17 (a). BS449 : Part 2: 1969)6.2.2 Contact Area of API Pipe on Capping Plate = 3401 mm^26.2.3 Stiffener projection beyond API pipe OD = 184 mm6.2.4 Required thickness of MS Stiffeners t(s) = 2.4 mm
Adopt 10 mm (4No. MS Stiffeners)
6.3 Thickness of Capping Plate6.3.1 Allow Shear Stress on Capping Plate = 125 MPa
(Table 10. BS449:Part 2:1969)6.3.2 Effect. Punching Shear Shear Perimeter = OD of API Pipe + Perimeter
- 8 x thickness of stiffeners = 1599 mm
6.3.3 Required Thickness of Capping Plate = 4.0 mm Adopt 10 mm
6.4 Allowable Bearing Stress on Capping Plate6.4.1 Allow. Bearing Stress on Capping Plate = 210 MPa
(Table 9. BS449:Part 2:1969)6.4.2 Proj. Bearing Area (API + Stiffeners) = 10761 mm^26.4.3 Actual Bearing Stress = 74 MPa
< All. Bearing Stress, OK
FOR INTERNAL USE ONLY
Page 5
Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
6.5 Check Stiffeners for Buckling6.5.1 Bearing Area of API Pile = 3401 mm^26.5.2 Bearing Area of 4No. Stiffeners = 7359 mm^2
Assume uniform distribution of Pile Axial Load,6.5.3 Compressive Load per Stiffener = 136.8 kN6.5.4 Pile head Embedment into Pilecap = 150 mm6.5.5 Assume Stiffener Depth, d = 140 mm
(Conservative Estimate)6.5.6 Slenderness Ratio of Stiffener
d ' @sgrt(3)1 thickness of stiffener = 24.26.5.7 Allow. Compressive Stress = 146 MPa
(Table 17(a). BS449)6.5.8 Allow. Buckling Load on Stiffener = 268.6 kN '
> Compressive Load of Stiffener, OK
6.6 Check Bearing on API PipeMoment equilibrium about intersection of Capping Plate and API Pipe,
6.6.1 Bearing Force on API Pipe = 180 kN6.6.2 Assume material for API Pipe to be equivalent to G55 steel,6.6.3 Allow. Bearing Stress = 320 MPa6.6.4 Allow Bearing Load = 448 kN
> Actual Bearing Force, OK
6.7 Fillet Weld Design (Stiffener to API Pipe)6.7.1 Weld Length per Stiffener = 2 x d
= 280 mm per stiffener6.7.2 Req'd Shear Load Capacity for weld = 0.49 kN/mm
Adopt 7 mm Fillet Weld
FOR INTERNAL USE ONLY
Page 6
Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
Design Report
1. IntroductionThis report presents the design criteria and design calculations for pile foundation for Interchange 3 of Project B 15 Road Upgrading Works.
Interchange 3 is a cloverleaf interchange with arch shaped R.C bridge as shown below
From structural analysis the compression load coming over the piles from one half of the bridge is 12600 ton while the other half is 2800 ton in tension.
2. Site ConditionThe topograph of the site is rolling to undulating. The subsoil condition is generalized as shown above.
The top 12m to 16m from the OGL of the residual soil is clayey silt with SPT 6-39 (average SPT=20): This is underlain by hard clayey silt sith SPT exceeding 50 up to 28m bgi.
3. AnalysisShallow foundation is not suitable because part of the formation is on filled ground and alsopart of the foundation is in tension or high compression.Driven spun piles cannot or not practical to provide adequate tension required. Large diameter bored piles are suitable for high compression and tension required.
4. Design Calculations4.1 Compression piles
The allowable compression load carrying capacity of the single pile has been calculated based on the SPT 'N" values, using the following formula.
FOR INTERNAL USE ONLY
Page 7
Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
Allowable load : Ab, af + As,fs3 2
Ab = base area (m2)
qf = unit base resistance= 400 Nb (in SI-unit), Meyerhof's Empirical Formula
Nb = average 'N' over 5m above and 3m below depth being considered (< 50)
As = Pile circumference area (m2)
fs = unit skin friction= 2 Nave (in SI-unit)
Nave = Average SPT value with depth
Factor of safety of base resistance = 3 to control settlementFactor of safety of friction resistance = 2
The detailed pile calculations are given in Appendix B.
4.2 Tension pilesThe allowable tension load carrying capacity of single pile has been calculated based on SPT 'N' values, using following formulaAllowable load = As . fs 2
As = Pile circumference area
fs = Unit skin friction= 2 Nave (in SI-unit)
Nave = Average SPT 'N' value with depth
Factory of safety against friction resistance = 2
The detailed pile calculations are given in Appendix B.
5. Design Calculations5.1 General Diameter of Compression pile : 1500 mm with design load of 900 ton Diameter of Tension piles : 1200m with design load of 400 ton Estimated pile length = 19m socketing 3 times diameter into hard stratum of SPT> 50
5.2 Preliminary Load Tests AnalysisCompression load tests and pull out tests were carried out at the Interchange bridge site to assess the performance of the piles installed to the design lengths.
FOR INTERNAL USE ONLY
Page 8
Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
(a) West AbutmentThe tension Test Piles (No.81) located on the west abutments satisfied the performance criteria. Based on Prof Chin's Stability Plot:
Ultimate load : 1141 tonne
Average Unit Shaft Friction : 16 tonne/m2
The compression Test Pile No. 15 located ont the west abutments satisfied criteria at work load and 2 x work load but just failed to satisfy the recovery criteria. Based on stability plot.
Ultimate capacity : 2,490 tonne
Ultimate Shaft capacity : 1,945 tonne
Mobilised Toe capacity : 548 tonne
Ultimate Unit Shaft Resistance : 39 tonne/m2
Mobilised Unit Toe Resistance : 310 tonne/m2
Based on these assessment, piles were constructed to following toe elevations: Compression Piles : RL 33.00(5m longer than Test Piles)
Tension Piles : RL 31.00 (same length as Test Pile)
(b) East AbutmentTension Pile No. 71 was tested. Pile satisfy the deflection criteria at working loadbut however failed to attain the 2 x working load without excessive movement. Based on Stability Plot, the following capacitities can be estimated:
Ultimate Shaft capacity : 624 tonne
Unit Shaft Resistance : 9 tonne/m2
This is much less than the 16.0 tonne/m2 value of tension pile No. 81. Based on the evaluated value of 9.0 tonne/m2, all remaining working tensionpiles are installed to RL 21.00 toe level, l O.Om longer than the test pile. Compression pile No. 65 was first tested. It failed to satisfy the performance criteria. Estimated capacities are:Ultimate capacity : 1600 tonne
Ultimate Shaft capacity : 625 tonne
Ultimate Toe capacity : 1041 tonne
FOR INTERNAL USE ONLY
Page 9
Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
Unit Shaft Resistance : 12 tonne/m2
Mobilised Unit Toe Resistance589 tonne/m2 Based on above results, Test Pile No. 2 (Pile No.66) located 4.50m from P65 was installed to toe level RL 33.00 (5.Om longer). Theoretical ultimate capacity should be of the order of 1,900 tonnes. The test showed the following:Ultimate capacity : 1520 tonne
Ultimate Shaft capacity : 730 tonne
Mobilised Toe capacity : 790 tonne
Ultimate Unit Shaft Resistance : 10 tonne/m2
Mobilised Unit Shaft Resistance : 447 tonne/m2
These are less than values obtained from P65, indicating significant variation in the subsoil strength. Concreting procedures are satisfactory and concrete batch recordsand test indicate supplied concrete complied with the requirements of the specification. Concreting volume of pile does not indicate occurrence of collapse of borehole or necking. Since the pile was concrete immediately after boring, strength relaxation due to aging should not occured.Based on above, all remaining piles are to be installed to toe levels 23. Pile No. P52 willbe test to assess amount of pile head movement at working load and 2 x working load. Estimated ultimate capacity of piles to toe level RL 23.00 is order 2,100 tonnes.
(c) Results of loads tests carried out at Interchange No. 3 are shown in Figure T1 to T.
FOR INTERNAL USE ONLY
Page 10
Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
FOR INTERNAL USE ONLY
Ro
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B-1
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46
112
22
83
1214
V.S
tiff
cla
yey s
ilt
SP
T
36
29
50
75
36
.28
72
.57
136
.66
99
1775
30
00
01.
76
753
014
176
71
49
58
22
63
010
16H
ard
cla
yey s
ilt
SP
T 5
0
35
30
50
75
37.5
375.0
614
1.3
710
612
75
30
00
01.
76
753
014
176
71
53
06
22
977
818
Hard
cla
yey s
ilt
SP
T 5
0
62
0H
ard
cla
yey s
ilt
SP
T 5
0
No
te:
42
2H
ard
cla
yey s
ilt
SP
T 5
0
1.
Co
rrecte
d N
= 1
5 +
0.5
(N
-15),
fo
r N
up
to
and
eq
ual to
4 t
imes N
=50
22
4H
ard
cla
yey s
ilt
SP
T 5
0
02
6H
ard
cla
yey s
ilt
SP
T 5
0
BH
-13
(West
sid
e)
BH
-13
(Eest
sid
e)
RD
Level 2
5.7
5m
UL
TIM
AT
E S
HA
FT
RE
SIS
TA
NC
EU
LT
IMA
TE
EN
D B
EA
RIN
G R
ES
IST
AN
CE
AL
LO
WA
BL
E L
OA
D
BH
-11(
West
sid
e)
Page 11
Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
FOR INTERNAL USE ONLY
Ro
ad
B-1
5
A
pp
en
dix
B
PIL
E L
EN
GT
H E
ST
IMA
TIO
N A
LO
NG
TH
E I
NT
ER
CH
AN
GE
#3
(WE
ST
SID
E O
F T
HE
CE
NT
RE
LIN
E O
F T
HE
RO
AD
)
where
A
b =
b
ase a
rea (
m^2
)
q
f =
4
00
*Nb
(SI-
Unit
s)
N
b =
S
PT
valu
e at
base
A
s =
p
ile c
ircum
fere
nce (
m^2
)
f
s = 2
*Nave (
SI-
Unit
s)
N
ave =
a
vera
ge s
pt
valu
e w
ith d
ep
th
A
llo
wab
le lo
ad
= U
ltim
ate
lo
ad
alo
ng
base/3
.0 +
Ult
imate
lo
ad
alo
ng
shaft
/2.0
A
llo
wab
le lo
ad
= A
b*q
f/3
+ A
s*f
s/2
F
S f
or
base r
esis
tain
3.0
0
F
S f
or
fric
tio
nal re
s 2
.00
B
ore
d p
ile d
iam
ete
r 1.
20
mete
rsS
UB
SO
IL P
RO
FIL
E A
LO
NG
TH
E B
RID
GE
LO
CA
TIO
N
Re
du
ce
d
Db
SP
TC
orr
ec
ted
Av
era
ge
Red
uced
Le
ve
l(m
)D
ep
thN
NN
av
efs
=2
NA
sQ
sN
bq
f=4
00
Nb
Ab
Qb
Ba
se
S
ha
ftT
ota
l(k
N)
Level(
m)
26
00
00
00
04
160
01.
131
1810
60
30
60
36
8B
ori
ng
B
ori
ng
25
18
63
63
.77
23
518
00
1.13
12
03
66
79
116
90
66
Dep
th(m
)R
D L
evel 6
4.8
9m
Dep
th(m
)R
D L
evel 6
6.5
0m
24
28
64
87.5
46
05
216
01.
131
24
43
814
30
84
46
40
0
23
36
64
.59
11.3
110
26
24
00
1.13
12
714
90
551
956
62
2M
ed
cla
yey s
ilt
SP
T 1
62
Med
cla
yey s
ilt
SP
T 1
0
22
49
95.4
10.8
15.0
816
37
26
86
1.13
13
03
710
128
110
94
60
4M
ed
cla
yey s
ilt
SP
T 1
74
Med
cla
yey s
ilt
SP
T 1
1
21
59
96
1218
.85
22
67
29
00
1.13
13
28
010
93
113
120
658
6S
tiff
cla
yey s
ilt
SP
T 2
36
Sti
ff c
layey s
ilt
SP
T 1
2
20
611
116
.71
13.4
32
2.6
23
04
93
450
1.13
13
90
213
01
152
1452
56
8S
tiff
cla
yey s
ilt
SP
T 2
98
V.S
tiff
cla
yey s
ilt
SP
T 3
9
197
1111
7.2
514
.52
6.3
93
83
104
050
1.13
14
58
015
27
191
1718
54
10V
.So
ft c
layey s
ilt
SP
T 2
10V
.Sti
ff c
layey s
ilt
SP
T 3
9
188
1111
7.6
715
.33
30
.16
46
212
46
50
1.13
152
59
1753
23
119
84
52
12V
.So
ft c
layey s
ilt
SP
T 2
12H
ard
cla
yey s
ilt
SP
T 5
0
179
21
188
.717
.43
3.9
359
014
550
01.
131
62
20
20
73
29
52
36
950
14V
.So
ft c
layey s
ilt
SP
T 2
14H
ard
cla
yey s
ilt
SP
T 5
0
1610
21
189
.55
19.0
93
7.7
72
016
62
25
1.13
170
40
23
47
36
02
70
74
816
Hard
cla
yey s
ilt
SP
T 4
716
Hard
cla
yey s
ilt
SP
T 5
0
1511
31
23
10.6
72
1.3
34
1.4
78
85
18710
01.
131
80
30
26
77
44
23
119
46
18H
ard
cla
yey s
ilt
SP
T 5
018
Hard
cla
yey s
ilt
SP
T 5
0
1412
32
23
.511
.65
23
.31
45.2
410
54
20
78
75
1.13
18
90
62
96
952
73
49
64
42
0H
ard
cla
yey s
ilt
SP
T 5
02
0H
ard
cla
yey s
ilt
SP
T 5
0
1313
38
26
.512
.71
25.4
34
9.0
112
46
22
89
50
1.13
110
122
33
74
62
33
99
74
22
2H
ard
cla
yey s
ilt
SP
T 5
02
2H
ard
cla
yey s
ilt
SP
T 5
0
1214
38
26
.513
.63
27.2
752
.78
143
92
510
02
51.
131
113
38
3779
72
04
49
94
02
4H
ard
cla
yey s
ilt
SP
T 5
02
4H
ard
cla
yey s
ilt
SP
T 5
0
1115
50
32
.514
.81
29
.63
58
.55
1675
27
10750
1.13
112
158
40
53
83
84
89
03
82
6H
ard
cla
yey s
ilt
SP
T 5
02
6H
ard
cla
yey s
ilt
SP
T 5
0
1016
50
32
.515
.85
31.
71
60
.32
1912
29
114
75
1.13
112
978
43
26
956
52
82
36
28
Hard
cla
yey s
ilt
SP
T 5
02
8H
ard
cla
yey s
ilt
SP
T 5
0
917
50
32
.516
.78
33
.56
64
.09
215
13
514
075
1.13
115
918
53
06
1075
63
81
34
So
il Investi
gati
on P
h:ll
So
il Investi
gati
on P
h:l
818
50
32
.517
.61
35.2
16
7.8
62
38
94
216
650
1.13
118
83
16
277
119
574
72
32
719
50
75
20
.48
40
.95
71.
63
29
33
48
190
75
1.13
12
1573
719
114
67
86
58
30
Bo
ring
62
050
75
23
.07
46
.14
75.4
34
79
54
215
00
1.13
12
43
168
105
174
09
84
52
8D
ep
th(m
)
52
150
75
25.4
350
.86
79
.17
40
27
59
23
62
51.
131
26
719
89
06
20
1310
92
02
60
42
250
75
27.5
955.1
78
2.9
44
576
64
25750
1.13
12
912
39
70
82
28
811
99
62
42
Med
cla
yey s
ilt
SP
T 6
32
350
75
29
.56
59
.13
86
.71
512
770
278
75
1.13
13
152
810
50
92
56
313
072
22
4M
ed
cla
yey s
ilt
SP
T 9
22
450
75
31.
38
62
.76
90
.48
56
78
75
30
00
01.
131
33
92
911
310
28
39
1414
92
06
Sti
ff c
layey s
ilt
SP
T 7
12
550
75
33
.06
66
.12
94
.25
62
31
75
30
00
01.
131
33
92
911
310
311
614
42
518
8S
tiff
cla
yey s
ilt
SP
T 1
1
02
650
75
34
.61
69
.22
98
.02
678
575
30
00
01.
131
33
92
911
310
33
93
1470
216
10V
.Sti
ff c
layey s
ilt
SP
T
-12
750
75
36
.05
72
.11
101.
79
73
40
75
30
00
01.
131
33
92
911
310
36
70
149
80
1412
V.S
tiff
cla
yey s
ilt
SP
T
-22
850
75
37.4
74
.79
105.5
678
95
75
30
00
01.
131
33
92
911
310
39
47
152
57
1214
V.S
tiff
cla
yey s
ilt
SP
T
-32
950
75
38
.65
77.3
109
.33
84
51
75
30
00
01.
131
33
92
911
310
42
26
1553
510
16H
ard
cla
yey s
ilt
SP
T 5
0
-43
050
75
39
.82
79
.65
113
.19
00
875
30
00
01.
131
33
92
911
310
450
415
814
818
Hard
cla
yey s
ilt
SP
T 5
0
62
0H
ard
cla
yey s
ilt
SP
T 5
0
No
te:
42
2H
ard
cla
yey s
ilt
SP
T 5
0
1.
Co
rrecte
d N
= 1
5 +
0.5
(N
-15),
fo
r N
up
to
and
eq
ual to
4 t
imes N
=50
22
4H
ard
cla
yey s
ilt
SP
T 5
0
02
6H
ard
cla
yey s
ilt
SP
T 5
0
BH
-13
(West
sid
e)
BH
-13
(Eest
sid
e)
RD
Level 2
5.7
5m
UL
TIM
AT
E S
HA
FT
RE
SIS
TA
NC
EU
LT
IMA
TE
EN
D B
EA
RIN
G R
ES
IST
AN
CE
AL
LO
WA
BL
E L
OA
D
BH
-11(
West
sid
e)
Page 12
Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
FOR INTERNAL USE ONLY
Ro
ad
B-1
5
A
pp
en
dix
B
PIL
E L
EN
GT
H E
ST
IMA
TIO
N A
LO
NG
TH
E I
NT
ER
CH
AN
GE
#3
(WE
ST
SID
E O
F T
HE
CE
NT
RE
LIN
E O
F T
HE
RO
AD
)
where
A
b =
b
ase a
rea (
m^2
)
q
f =
4
00
*Nb
(SI-
Unit
s)
N
b =
S
PT
valu
e at
base
A
s =
p
ile c
ircum
fere
nce (
m^2
)
f
s = 2
*Nave (
SI-
Unit
s)
N
ave =
a
vera
ge s
pt
valu
e w
ith d
ep
th
A
llo
wab
le lo
ad
= U
ltim
ate
lo
ad
alo
ng
base/3
.0 +
Ult
imate
lo
ad
alo
ng
shaft
/2.0
A
llo
wab
le lo
ad
= A
b*q
f/3
+ A
s*f
s/2
F
S f
or
base r
esis
tain
3.0
0
F
S f
or
fric
tio
nal re
s 2
.00
B
ore
d p
ile d
iam
ete
r 1.
20
mete
rsS
UB
SO
IL P
RO
FIL
E A
LO
NG
TH
E B
RID
GE
LO
CA
TIO
N
Re
du
ce
d
Db
SP
TC
orr
ec
ted
Av
era
ge
Red
uced
Le
ve
l(m
)D
ep
thN
NN
av
efs
=2
NA
sQ
sN
bq
f=4
00
Nb
Ab
Qb
Ba
se
S
ha
ftT
ota
l(k
N)
Level(
m)
48
050
32
.53
2.5
65
00
33
130
00
1.13
114
70
34
90
10
49
01
68
Bo
ring
B
ori
ng
47
150
32
.53
2.5
65
3.7
72
45
33
130
00
1.13
114
70
34
90
112
350
23
66
Dep
th(m
)R
D L
evel 6
4.8
9m
Dep
th(m
)R
D L
evel 6
6.5
0m
46
250
32
.53
2.5
65
7.5
44
90
33
130
00
1.13
114
70
34
90
12
45
514
66
40
0
45
350
32
.53
2.5
65
11.3
173
54
015
83
31.
131
179
07
59
69
36
86
33
76
22
Med
cla
yey s
ilt
SP
T 1
62
Med
cla
yey s
ilt
SP
T 1
0
44
450
32
.53
2.5
65
15.0
89
80
45
178
57
1.13
12
019
66
73
24
90
72
22
60
4M
ed
cla
yey s
ilt
SP
T 1
74
Med
cla
yey s
ilt
SP
T 1
1
43
550
75
39
.58
79
.17
18.8
514
92
48
193
75
1.13
12
1913
73
04
74
68
050
58
6S
tiff
cla
yey s
ilt
SP
T 2
36
Sti
ff c
layey s
ilt
SP
T 1
2
42
650
75
44
.64
89
.29
22
.62
20
20
54
215
00
1.13
12
43
168
105
1010
911
556
8S
tiff
cla
yey s
ilt
SP
T 2
98
V.S
tiff
cla
yey s
ilt
SP
T 3
9
41
750
75
48
.44
96
.88
26
.39
2558
59
23
62
51.
131
26
719
89
06
1278
1018
554
10V
.So
ft c
layey s
ilt
SP
T 2
10V
.Sti
ff c
layey s
ilt
SP
T 3
9
40
850
75
51.
39
102
.78
30
.16
310
06
42
5750
1.13
12
912
39
70
815
50
112
57
52
12V
.So
ft c
layey s
ilt
SP
T 2
12H
ard
cla
yey s
ilt
SP
T 5
0
39
950
75
53
.75
107.5
33
.93
36
47
70
278
75
1.13
13
152
610
50
918
24
123
32
50
14V
.So
ft c
layey s
ilt
SP
T 2
14H
ard
cla
yey s
ilt
SP
T 5
0
38
1050
75
55.6
811
1.3
63
7.7
419
875
30
00
01.
131
33
92
911
310
20
99
134
09
48
16H
ard
cla
yey s
ilt
SP
T 4
716
Hard
cla
yey s
ilt
SP
T 5
0
37
1150
75
57.2
911
4.5
84
1.4
74
752
75
30
00
01.
131
33
92
911
310
23
76
136
86
46
18H
ard
cla
yey s
ilt
SP
T 5
018
Hard
cla
yey s
ilt
SP
T 5
0
36
1250
75
58
.65
117.3
14
5.2
453
07
75
30
00
01.
131
33
92
911
310
26
53
139
63
44
20
Hard
cla
yey s
ilt
SP
T 5
02
0H
ard
cla
yey s
ilt
SP
T 5
0
35
1350
75
59
.82
119
.64
49
.01
58
64
75
30
00
01.
131
33
92
911
310
29
32
142
42
42
22
Hard
cla
yey s
ilt
SP
T 5
02
2H
ard
cla
yey s
ilt
SP
T 5
0
34
1450
75
60
.83
121.
67
52
.78
64
21
75
30
00
01.
131
33
92
911
310
32
1114
52
04
02
4H
ard
cla
yey s
ilt
SP
T 5
02
4H
ard
cla
yey s
ilt
SP
T 5
0
33
1550
75
61.
72
123
.44
56
.55
69
80
75
30
00
01.
131
33
92
911
310
34
90
148
00
38
26
Hard
cla
yey s
ilt
SP
T 5
02
6H
ard
cla
yey s
ilt
SP
T 5
0
32
1650
75
62
.512
56
0.3
2754
075
30
00
01.
131
33
92
911
310
3770
150
80
36
28
Hard
cla
yey s
ilt
SP
T 5
02
8H
ard
cla
yey s
ilt
SP
T 5
0
31
1750
75
63
.19
126
.39
64
.09
810
075
30
00
01.
131
33
92
911
310
40
50
153
60
34
So
il Investi
gati
on P
h:ll
So
il Investi
gati
on P
h:l
30
1850
75
6..8
212
7.6
36
7.8
68
66
175
30
00
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131
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43
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156
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1950
75
64
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Dep
th(m
)
27
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65.3
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94
.25
1259
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62
98
176
08
188
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ff c
layey s
ilt
SP
T 1
1
22
26
50
75
67.1
313
4.2
69
8.0
213
160
75
30
00
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131
33
92
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658
017
89
016
10V
.Sti
ff c
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ilt
SP
T
21
27
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4.8
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1.79
1372
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30
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33
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66
62
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114
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.Sti
ff c
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20
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67.6
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5.3
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5.5
614
28
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714
318
453
1214
V.S
tiff
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192
950
75
67.9
213
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310
9.3
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850
75
30
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74
25
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510
16H
ard
cla
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ilt
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T 5
0
183
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68
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.115
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818
Hard
cla
yey s
ilt
SP
T 5
0
62
0H
ard
cla
yey s
ilt
SP
T 5
0
No
te:
42
2H
ard
cla
yey s
ilt
SP
T 5
0
1.
Co
rrecte
d N
= 1
5 +
0.5
(N
-15),
fo
r N
up
to
and
eq
ual to
4 t
imes N
=50
22
4H
ard
cla
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ilt
SP
T 5
0
02
6H
ard
cla
yey s
ilt
SP
T 5
0
BH
-13
(West
sid
e)
BH
-13
(Eest
sid
e)
RD
Level 2
5.7
5m
UL
TIM
AT
E S
HA
FT
RE
SIS
TA
NC
EU
LT
IMA
TE
EN
D B
EA
RIN
G R
ES
IST
AN
CE
AL
LO
WA
BL
E L
OA
D
BH
-11(
West
sid
e)
Page 13
Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
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Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
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Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
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Cawangan Jalan, Ibu Pejabat JKR, K.L
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Page 17
Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
5) Check for buckling load
Qub = Cu ElWhere = = 10
CU = 15 kPa
E = 210 kN/mm2
I = 1/64 B (d14 - d24)
Qub = 10 15 x 210 x B (101.64 - 85.444) 64 106
= 907 kN
Allowable Qb = 907___ 2
= 454 kN > 300 kN
OK
6) Check for elastic compression
e = PL P = 300 kNL = 10m
EP A = 31416 mm2
Ep = 35.3 kN/mm2
= 300 x10 x103
31416 x 35.3
= 3 mm
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Page 18
Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
Sample Pile Design Calculations
1. Project : KKS Road ProjectPiled Embankment for the approaches to Sg. Likas Bridge.
2. Generalized subsoil profile.
* Flat alluvial formation
* Top 24m consists of soft to very soft alluvium with few localized sandy lenses (Cu =10-20 kPa with an average of about 15 kPa except at lenses of sand). Stiff to hard strata of about 2 - 4m thick overlying on highly to moderately weathered sandstone/shale bedrock. WT is near the ground surface.
3. AnalysisStability and settlement analysis have concluded that simple ground treatments by partial sand replacement with high strength woven polyester geotextile reinforcement or vertical drains are not possible to achieve FOS = 1.5 and or post construction settlement to be less than 200mm for the first 5 years of service if height of embankment exceeds 4.2m.
Piled raft embankment is adopted in preference to EPS, elevated structure and stone columntreatment because:a) EPS embankment is technically not acceptable because the site is subject to flooding
& the cost is high.
b) Elevated structure is about 30% more expensive (separate analysis)
c) Though treatment by stone columns is cheaper, it requires longer time to consolidate and technically less superior
4. Design calculation Analysis has shown that driven R.C piles will be the most cost effective.
The site has no vibration or noise or ground heave constraints. Pile capacity of about 600 kN is chosen to get optimum pile spacing of 2 to 3m and raft thickness of 350 - 450mm for pile depth of about 30m.
Use 250X250 R.C piles at spacing "x" bothways Max design capacity - 625 kN.
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Piled embankmentBridge
V.soft to soft clay
Sandstone/shaleStiff to hard
Sand Lenses
CL
Page 19
Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
Load on each pile = x2.d.h, where x = spacingd = soil density
= 20kN/m3 hh = embankment height
625 = x2.20.h
x = (31.25/h)1/2 For h = 6.5m, x = 2.19m, say 2.0m
For h = 6.0m, x = 2.2m, say 2.0m For h = 5.5m, x = 2.38m, say 2.25m For h = 5.0m, x = 2.50m, say 2.25mFor h = 4.5m, x = 2.64m, say 2.25m (allow some traffic load of 10 kPa)
Conclusion:Use 250x250 R.C x 30m long at 2.0m spacing for h=6.5 - 6.0m & 2.25m spacing for h = 4-6m(Pile capacity calculations enclosed).
R.C piles (MS 1314, Class 1) are designed as end bearing piles driven to set.
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Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
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Page 21
Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
Design of Micropile
a) Design load per pile = 800kNb) Diameter of micropile = 200mmc) Main reinforcement = 3 Nos of 50mm diam. deformed bars of yield
stress fy = 410N/mm2.d) Factor of safety = 2.5 (min)e) Grout characteristic strength, fcu = 20N/mm2.
Check Structural Capacity
Area of reinf, Asc = B/4 x 502 x 3 = 5892mm2
fcu = 20N/mm2
Area of grout, Ag = B /4 x 2002
= 31,416mm2..Area of net grout = 31,416 - 5892
= 25,524mm2According to BS 8110, clause 3.8. 4.3Ultimate axial load, Pu = 0.4 fcu Ac + 0.75Asc fy
= 0.4x20x25,524 + 0.75x5892x410 = 2,016kN.
.. Factor of safety = Pu/800= 2.53> 2.5 O.K.
Check Bond Length Required- Depth of micropile = 20m
At least l0m will be embedded in very hard decomposed granite SPT, N > 50.
- Bond between grout & hard formation = 0.4N/mm2
.. Min required bond length in hardformation, Ib = 800 x 2.5 x l 000NB x 200 x 0.4
= 7958mm = 8.0m.< 10m provided O.K.
Design of M.S. Plate for Pile HeadUse 250mm x 250mm x 20mm M.S. plate Stress on plate = 800 x l03N
250 x 250 = 12.8N/mm2< 155N/mm2 O.K. (allowable stress BS449)
Details of Micropiles & works specification are encl
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Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
Works Specification for Design and Installation of 200mm Diameter Micropiles1. Scope of work shall include design & installation of 200mm diam micropiles of 20m provi
sional length. The micropiles shall be reinforced with 3 Nos. of 50mm diam deformed bars (fy = 410N/mm2) The working load of the micropile is 800KN.
2. DrillingInitial drilling involves installation of 242mm diam conductorcasing through loose soil (about 1.5m) by means of rotary boring or equivalent. Upon reaching hard/stiff formation down the hole hammer will be used to advance the borehole till a minimum penetration of 10m in very hard decomposed granite. The drilled hole will be flush clean by compressed air before the reinforcement bars are inserted into the hole. Suitable coupling device will be used. During drilling, a complete record of soil strata will, be taken for Engineer's inspection.
3. Grout MixOrdinary Postland cement with water cement ratio of 0.5 will be used Non-shrink cement admixture will be added to improve bonding.
4. Grouting ProcedureA high speed Koken grout mixer is used for the mixing of the cement grout. The capacity of the grout mixer is about 25-0 litres.
For grout mixing, 100 litres of water with some non shrink admixture is poured into the mixer follow by 4 bags of 50 kg. ordinary Portland cement then allow to mix throughly, normally a few minutes. After mixing, the cement grout, a pressure hose is connected to thegrouting pipe which acts as tremie pipe for grouting. The other end of the pressure hose is connected to a diesel engine high pressure pump.
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Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
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Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
Micropile Design Calculations
Micropile design for underpinning works for an old building is shown as follows. The subsoil con-sists of about 3m of very soft clay, 5m to 8m of stiff to hard sandy clay with gravels (SPT = 11 to42). The bedrock generally consists of highly weathered and fractured sandstone/shale (RQD = 0 -25%, UCS = 7.5 Mpa).
1) Micropile detailsDiameter of micropile = 200 mmDesign load of micropile = 300 kNPipe diameter = 101.6 mmPipe wall thickness = 8.08 mmSteel grade (API pipe) = N80Yield strength = 500 N/mm2
(a) Check for structural capacity Ultimate structural capacity
PU = B (101.62 -85.44 2) X 500 kN
4 1000
= 1187 kN
Applying factor of safety of 2.5.
Allowable structural capacity.
PA = 1187
2.5
= 475 kN > 300 kN
OK
(b) Check for geotechnical capacityBased on boreholes BH1 and BI-12, the depth of bedrock (sandstone/shale) varies from 8.7 m to 11.0 m b.g.l. Since the overburden soil consists of about 3.0 m of verysoft soil, the shaft friction on the remaining overburden soil (5 to 8 m) with N value of 11 to 42 should be ignored and the micropiles are designed to be socketed into thebedrock.
The socketing length in rock, L, is worked out as follows:
FS Qa = 0.05 qa B D x L + 0.5qa B D2
4
where FS is the factor of safety = 2.5
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Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
Qa = Allowable geotechnical capacityqa = Unconfined compressive strength of rock
= 7.5 Mpa for sandstone/shale
Bond stress = 5% of UCS of rock
D = Diameter of micropile hole
2.5 x 300 = 0.05 x 7.5 x 103 x B x0.2 L + 0.5 x 7.5 x 103 x B x 0.22
4
750 = 235.6 L + 117.8
L = 2.68 m
Designed socketing length of pile = 3.0 m
2) Check overall underpinning pile supportEstimated total load of the whole building (3 storey). = 2,000 tons
No. of micropile points = 95Load on each pile = 2,000
95
= 21 tons
Working load for each micropile provided = 30 tons
OK
3) Check for anchorage bond between underpinning pile and the existing foundatic Since epoxy grout is used to fill the hole formed by the micropile in the existir foundation and the strength of epoxy grout is much higher than the concrete strength, it can be considered as monolithic for the whole foundation.
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Page 26
Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
4) Check for shear failure of existing foundation.
Perimeter for shear check, p = 1900 mm
Effective depth of foundation, d = 1050-50-10= 990 mm
Maximum reaction load, V = 300 kN
Shear stress, V = V
Pd
= 300 x 103
1900 x 990
= 0.16 N/mm2
From Table 3.9, BS 8110 for d > 400 mm and100As/bd = 0.25 (nominal reinforcement), allowable shear stress Vc = 0.40 N/mm
2
V
Page 27
Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
FOR INTERNAL USE ONLY
ItemNo.
A. Design and install cast in-situ 800kN workingcapacity micropiles complete withreinforcement as shown on the drawings inprovisional lengths 20.0m and pressure-grouted with and including approved groutingmaterial, drilling in all types of soils androck and all coring casings, linings, plugs,etc. and disposal of all excavated materialand debris from site.
Design information:-
a) Diameter of piles: 200mmb) Main bars: 3Y50c) Links: R05 helical link @ 100mm c/cd) Steel casings: 292mm O.D x 9mm thicke) Grout: Cement grout, w/c = 0.5, fcu = 20N/m2
f) Grout additives: Non shrink admixtureg) Factor of safety : 2.5h) Bond strength: 0.9N/mm2
i) Bond length: 10mj) Ultimate load: 2016kNk) Capacity: 800kNl) Working load: 800kNm) etc
Design and install all capping plates andstarter barsDesign information:-
Plate size: 250 x 250mmPlate thickness: 25mm
B. Starter bar size: 3Y50 or 8Y25
$ Description Quantity Unit Rate
Page 28
Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
Projek : Cadangan Blok Tambahan pada HospitalBersalin di Hospital Besar, K.Lumpur.
1.0 TujuanLaporan ini bertujuan untuk menyampaikan laporan penyiasatan tanah dan syor-syor asas yang sesuai bagi:Projek blok tambahan pada hospital bersalin, Kuala Lumpur.
2.0 Skop ProjekPerlaksanaan projek ini melibatkan pembinaan blok tambahan 2 tingkat di Hospital Bersalin. Blok yang dicadangkan ini dikelilingi oleh bangunan sedia ada.
3.0 Keadaan Tanah3.1 Sebanyak 3 ujian gerekan dalam telah dijalankan. Hasil ujian menunjukkan
keadaan lapisan tanah seperti berikut :-Ukurdalam(m) Jenis Tanah SPT (blows/ft.)0 - 4.5 Very soft CLAY 0 - 44.5 - 9/10.5 Loose SAND 1 - 79/10.5-13.5/16.0 Stiff silt or CLAY 1 - 913.5/16.0 Limestone RQD = 73 - 100%.>16.0 Limestone -
3.2 Kedudukan aras air bawah tanah ialah 1.45m.
4.0 syor-syor Asas4.1 Penapak konkrit tetulang adalah tidak sesuai kerana keupayaan galas yang rendah
dan jugs paras air bawah-tanah adalah tinggi.
"Driven R.C. or steel piles" adalah juga tidak sesuai kerana masalah "noise & vibration" dikawasan Hospital sukar diterima. "Inclined bedrock" juga mungkin mengakibat "excessive pile deviations".
Syor-syor asas yang dicadangkan adalah seperti berikut :-
Jenis Bangunan Jenis Asas Saiz Panjang Keupayaan Geseran Beba (mm) (m) galas yg Kulit Ujian
dibenarkan negatif
Blok Tambahan Cerucuk 200 16.5-19 200kN - 400kNmikro with 102 (micropile) API paip
(4)
4.2 Cerucuk mikro hendaklah digerudi sehingga ke paras batukapur dan dikunci (key) minima 3m ke dalam batukapur.
4.3 Sekurang-kurangnya 2 bilangan cerucuk digunakan untuk setiap tiang.
4.4 Jack pile (200x200xl5m) juga boleh diterima sebagai cerucuk gantian.
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Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
5.0 Syor-syor Tambahan5.1 Jika rongga (cavity) ditemui, cerucuk hendaklah dipanjangkan
melebihi rongga dan dikunci (keyed) minima 3m ke dalam batukapur tanpa rongga. (rujuk Fig. 1).
5.2 Untuk mengatasi masalah penanaman micropile dirongga, penender mestilah diarah mengemukakan cadangan sistem 'micropile installation' dan teknik-teknik 'grouting' dirongga semasa tawaran dibuat.
6.0 Hal-hal lainSatu set rekod penanaman cerucuk-cerucuk yang diuji berserta ujian beban hendaklah dihantar ke Unit Makmal bagi tujuan dokumentasi.
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Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
Lampiran A
Micropile Specfication
1. GeneralThe work involves the construction of 200mm (8") diameter micropile. The micropile shall be fabricated using steel tube and the bond length of micropile shall be 16m or directedby the S.O. The working load of micropile is 200 kN and factor of safety used in design is 2.0. The whole of work and materials shall be in, accordance with curreht Malaysian or British Standard or other National Standards approved by the S.O.
2. ReinforcementSteel grade - HFS 16 (BS: 1775 - 1964) External diameter 139mm (51/2)Thickness - 9.5mm (3/8") 2Yield strength - 250 N/mm (16 Tsi)
3. GroutThe grout shall be thcFoughly mixed with Ordinary Portland Cement (MS522) and water (MS28). The grout shall be Antishrink cement grout. The water cement ratio shall be 0245 -0.50. The 28 days. Strength for cement grout shall be 25N/mm (3570 psi). The representative cubes shall be collected on each day of grouting works for testing on the 28th days. Details of admixture shall be submitted to the S.O. for approval before commencement of works. The use of the admixture shall comply with instruction by the manufacturer & MS 922. The grout shall be free from segregation, slumping, & bleeding of water and fine materials during and after placing.
4. Installation a) Drilling
The drilling for installation of micropile shall guarantee the absence of Vibration which may cause damage to the existing building. Adequate precaution must be taken to ensure boreholes for micropile do not collapse during drilling.
If necessary, temporary casing shall be used. During drilling of borehole, the contractor shall maintain complete record of soil profile. The logging shall include depth of soil and water table. This drilled hole Viand! soil bore log shall be signed by contractor's site representative and a copy of which shall be deposited with the S.O. The contractor shall be required to keep representative sample of soil for each soil profil in plastic bag for inspection by.the S.O. Sample may only be disposed after the S.O. is satisfied that the logging has been properly done. The type-of drilling equipment shall be approved by the S.O. The drilled hole shall be flushed ckean.with air or water.
b) Fabrication of micro pileMethod of splicing of bars or pipes shall be approved by the S.O. Centralisers at about 3m centre must be used to ensure a minimum cover of 25mm or directed by the S.O.
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Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
c) GroutingThe contractor shall also provide details on method and equipment used in grout mixing. Further information such as grouting pressure, grouting procedure, grouting equipment and techniques employed in grouting under water shall also be furnished and approved by the S.O.
'To prevent deterioration of strength of soil, soil coring, installation of reinforcement and cement grouting shall be carried out in one continous operation.
5. Load TestingMicro-pile shall be load tested to 2 times design load using the Maintain Load Test. Minimum of one (1) load test shall be carried out. The contractor shall also specify and provide details of the method of load testing. Micropile shall be constructed only after the preliminary pile pass the load test requirements of JKR standard specification for building Works.
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Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
FOR INTERNAL USE ONLY
Bil. Unit Quantity Rate $
1 MICROPILES
(ALL PROVISIONAL)
A. Allow for Preliminaries Item
B. Provide all necessary pilingequipment on site, maintain on site,dismantle and remove from site oncompletion, allow for all standingor idling time and cost of operationfor the whole of piling works. Item
C. Installation of 200mm diameterMicropiles in soil, including coring,4" diameter pipe, steel plate head,jointing and extension and grouting MRin cement, all as specified (50positions)
D. Provide all necessary pile testingequipment on site, dismantle andremove from site on completion.Test 200mm diameter Micropiles in soilas specified. NO
Contoh Jadual Sebut Harga
Description
Page 33
Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
Lampiran E1
Pile Designfor
SMK (Perempuan Raja Zarina) Kelang
1. This project consists of construction of one additional 3-storey school block.
2. Max column load = 57 ton
3. This is a typical coastal alluvium site where first 60ft to 100 ft consists of very soft clay
4. Deep Sounding is very suitable and 4 nos of D/S results give consistent results as shown in Lampiran E-1
5. The site is a flat land and the first 4 ft is imported fill (about 5 years ago) Negative friction has to be checked.
6. Selection of piles (Refer to Fig. 1)6.1 Non displacement piles not suitable because of low column load and very soft clay
near the first 100 ft.
6.2 Timber pile also not suitable bacause its max length is about 40 ft. only.
6.3 Use 12" x 12" x 100 ft R.C. piles Design load = 30 Ton/pile (max)
7. Check Pile Capacity (Refer to Lampiran E-1) From D/S results
Qu = Qs + Qp
where Qu = ultimate capacity
Qs = skin friction
Qp = end resistance
FOR INTERNAL USE ONLY
Page 34
Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
7.1 Skin friction, QsBased on total friction (remoulded)
At 30m (100ft), total friction = 3,000 kg.
Qs = tube friction x-pile perimeter
tube perimeter
= 3,000 x (12" x 2.54 x 4)
11.3
= 32,300 kg
= 30 Ton.
Based on local friction (undisturbed)
Qs = (8.5 x 0.05 + 7.5 x 0.13 + 13 x 0.27 + 0.9) x 3.28 x 4 x 0.92
= 70 Ton
Sensitivity = Qs (undisturbed)
Qs (remoulded)
= 70
30
= 2.3, within usual range
Q's = " Qs, where " = 0.7 (Bjerrum)= 0.7 x 70= 49 Ton
7.2 End Resistance, Qp,
Qp = 80 (kg/cm2) x 1 ft2 x 0.92
= 73.6 Ton
Qu= 49 + 73.6 = 122.6 Ton
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Page 35
Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
7.3 Negative frictionNegative friction for piles at spacing more than 3 x diameters is
fn = 0.2 Po (Bjerrum)where Po = effective overburden
= h= 100' (100psf - 62.4 psf) = 3760 psf
Max. fn = 0.2 Po= 0.2 x 3760 = 752 psf
Average fn = (0 + 752)/2 = 376 psf
Total negative friction = fn x As= 376 x (100 x 4) = 150,400 lb= 67 Ton
7.4 Allowable load, QsThe negative skin friction, QN should only considered in combination with dead load because QN acts mainly at the lower portion of the pile and would only affect the settlement.2.5 QD.L = Qu- QN
QD.L = 70% Qa
2.5 x 0.7Qa = Qu - QNQa = (Qu - QN) /1.75
= (122.6 - 67)/1.75 = 31 Ton
say 30 Ton/pile
Notes : The filling is done about 5 years ago. At least 60 - 70% consolidation completed.
fn used is about the same as the undrained shear strength. Hence QN estimated is on the light side.To prevent tensile stress and buckling during driving, free drop hammers is preferred.
8. RecommendationUse 12" x 12" x 100 ft R.C. pilesFriction piles, driven to the required pene:,tration and load test to verify the capacity. (No "set" required).# Load tests after 4 weeks of driving.
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Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
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Pile Design Report
Cawangan Jalan, Ibu Pejabat JKR, K.L
Memo
Daripada: Penolong Pengarah Makmal,Caw. Rekabentuk & Penyelidikan, IP. JKR
Kepada: Penolong Pengarah(Binaan), Ibu Pejabat JKR, K.L.
Bil surat: (X) dlm. PKR.RB 4112 Tarikh : 26.3.1983
Per: Cadangan Masjid Baru di Batu 31/2, Jalan Cheras, K.L.Berhubung dengan perkara yang tersebut di atas, sukacita dimaklumkan bahawa cadangan asas yang disyorkan adalah seperti berikut:-
1. Keputusan penyiasatan tanahSebanyak 28 Nos. Proba JKR dan 5 Nos. Deep Boring telah dijalankan ditapak projekitu. Keputusan - keputusan yang diterima menunjukkan bahawa kawasan projek ini adalah terdiri daripada batu kapur. Paras batu kapur adalah daripada 2.5m hingga 14m daripada paras permukaan tanah sedia ada. Oleh kerana keadaan batu dasar yang susah untuk diramalkan, langkah-langkah pengawasan dan faktor keselamatan yang lebih tinggi perlu diambil di dalam rekabentuk asas.
2. Syor-syor asas2.1 Jenis - jenis asas yang disyorkan adalah seperti dicatitkan di dalam Lampiran A.
Sebelum kerja - kerja piling dimulakan sekurang - kurangnya satu ujian Proba JKR perlu dijalankan di setiap kedudukan tiang untuk menentukan paras batu dasar (>400 blows/kaki). Sekiranya paras batu dasar didapati kurang daripada 4.5m dibawah permukaan bumi, adalah dicadangkan supaya menggunakan R.C.cylinder foundation (sila lihat Lampiran A & B)
2.2 Sekurang - kurangnya 2 cerucuk perlulah digunakan ditiap-tiap kedudukan tiang kecuali jika R.C.cylinder foundation digunakan. Tiap - tiap tiang hendaklah diikat dengan rasak bawah dikedua - dua arah. Ini adalah sebagai langkah awas oleh kerana terdapat rongga - rongga dan kemungkinan masalah surutan.
2.3 Untuk memperolehi pengawasan yang lebih baik semasa memacu cerucuk tukul jatuh bebas(free drop hammer) dicadangkan supaya digunakan. Ini ialah supaya cerucuk tidakmenerima hentaman dan menyimpang berlebihan (overdriving and excessive deviation) oleh kerana keadaan batu dasar yang mencerun (inclined bedrock surfaces).
2.4 Hujung cerucuk keluli hendaklah dikelulikan dengan plat yang lebih. Ini adalah perlu untuk menahan tegasan yang berlebihan (withstand overstressing) apabila cerucuk sampai ke paras batu dasar.
2.5 Sekurang - kurangnya 2 nos. kumpulan cerucuk (pile group, NCT single pile) perlulah dipilih untuk ujian beban. Satu set driving records dan keputusan ujian beban hendaklah dihantar kepada Unit Makmal ini untuk analisa dan sebagai rekod di Unit Makmal.
2.6 Perhatian hendaklah diberi kepada pengalaman yang lepas iaitu cerucuk - cerucuk tambahan mungkin diperlukan untuk menggantikan cerucuk - cerucuk yang menyimpang
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berlebihan dan cerucuk - cerucuk yang masih tidak set diparas yang dalam (>10m). Adalah dicadangan supaya tambahan sebanyak 25m disertakan didalam B.Q.
2.7 Oleh kerana keadaan tanah yang rumit (tricky) jurutera tapak bina hendaklah selalu rujuk kepada keputusan penyelidikan tapak semasa menyelia kerja - kerja pembinaan asas. Apabila cerucuk dijangka sampai paras batu dasar, kejatuhan pemukul (drop of hammer) hendaklah dikurangkan. Tujuan langkah ini ialah untuk better keying & bedding effect on rock surface. Langkah ini juga akan mengurangkan cerucuk daripada menyimpang berlebihan.
Sekian disampaikan ulasan kami untuk tindakan tuan selanjutnya.
Berkhidmat Untuk Negara
......................................................(Ir. Neoh Cheng Aik),Jurutera Kerja Kanan (R1),bp. Penolong Pengarah (Makmal),Ibu Pejabat JKR, K.L.
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Lampiran A
Cadangan Asas Untuk Pro jekMas jid Batu 31/2, Jalan Cheras,K.L.
1. Bangunan Masjid (13T - 105T)Sila gunakan cerucul; keluli 203mm x 203mm x 45kg/m (Grade 43A9 BS 4360) dengan beban keupayaan 210 0/eerucuk. Untuk tujuan tawaran, panjang cerucuk ialah 8.5m(27ft) ATAU "R-C- cylinder foundation".Sila lihat Para 2.1
2. Bangunan Quarters Kelas G(9T - 16T)Sila gunakan eerucuk I-,yu berubat (treated timber pile) 125m x 125m dengan beban keupayaan 5W/oerucuk. Untuk tujuan taviarany panjang cerucuk ialah 8.5m (27 ft).
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Lampiran E 5
Extension of Terminal Building, Subang Airport
1. GeneralThe project consists of extension of International and Domestic Transper Corridor for Subang International Airport. The proposed-site is situated approximately 13 miles west of Kuala Lumpur.
Due to the close proximity of the proposed site to the existing terminal building v where theControl Tower for the airport is located, severe vibration such as driving piles is unacceptabldo Bored and Cast-in-situ piles were considered most suitable.
2. Soil ConditionThe site consists of residual soils of granite.Lampiran E5-1 represents the generalised poil profile. The top layer of the soil consists of brown firm sandy silty clay with some organic matters. The depth of this top soil varies from 6" to 2ft. Beneath this top soil underlies the yellowish with patches of grey medium sandy clayey silt with some gravelse This medium sandy clayey silt extend to a depth of 40 to 85 ft. below R.L. 86.00'. Between these layers of medium sandy clayey silt and the fractured or slightly weathered granite bedrocksq lies the greyish very stiff decomposed granite residual soil. The thickness of this decomposed granite residual soil varies. Water table is about Oft. b.g.l.
3. Load Settlement CriteriaThe system of piling to be designed shall meet the followings:-a) Safety Factor
The factor of safety for the purpose of computing the working load shall be taken as 2.5.
b) Working LoadThe working load adopted for single pile shall not be greater than the ultimate load divided by the safety factor of 2.5 and the ultimate load is defined as:(i) Load at which the gross settlement continues to increase without any further
increase in load.
(ii) Load at which gross settlement is 10% of the pile diameter.
c) Settlement Criteria(i) Gross settlement of the pile at working load during the first cycle of load
ing, loading to one time working load, shall not exceed 0.5".
(ii) The residual settlement of the pile at the end of the first cycle of loading shall not exceed 0.10".
(iii) The gross settlement of the pile at twice the working load shall not exceed 1.5"
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d) Group Effect
Negligible because of small group (2 or 3 pile per group) & large spacing 2.5 .
4. Structural Capacity of PilesSince piles are not fully reinforced, the structural capacity of the piles will be solely depend on the concrete section of the piles* In this case, the pile is reinforced for the top 40ft. only for the dispersion of the possible slight bending moment elperienced at the pile top.
The piles will be designed as short columns. According to CP 2004, the structural carrying capacity of Cast-in-situ concrete pile, that is, the safe working load per pile, W
W - 1/4 (Acc.Uw)
Where Acc = Gross cross section of the area of concreteUw = Specified cube crushing strength at 28 days.
= 3000 psi.
For d = 18, max. structural load = 80 Ton. d = 24, max. structural load = 150 Ton d = 30, max structural load = 230 Ton.
5. Check Pile CapacityUse 18" bored piles x85 ft max. Meyerhofs formula (modified) is applicable for bored piles in residual soilQu = Qs + Qp
= fs As.+ Op Ap
= N As + N. Ap50
where N = average SPT along pile shaft
N = average SPT near pile base (4 above pile base & 2 below pile base).
As = pile shaft area (ft2)
As = pile base area (ft2)
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Based on DB1218" x 75'
N = 16 fs = N = 0.32 TSF50
N = 50 qp = 50 TSB
Qs = fs As= 0.32 x (1.5' x 3.1416 x 75) = 113 Ton
Qp = 50 x (1/4 x 1.52 x 3.1416) = 88 Ton
Qa = Qs/20 + Qp/3.0 = 56.5 + 29.3= 85.8 Ton say 80 Ton
Based on DB 1018" x 55ft
N = 20 fs = 0.4 TSF
N = 80 qp = 80 TSF= 0-4 x (1o5 x 301416 x 55) =104 Ton
Qp = 80 x (1/4 x 1o5 x 1o5 x 3o1416) = 141 Ton
Qa = Qs/2.0 + Op/3.0 = 52 + 47 = 99 Tonsay 80 Ton.
Based on DB 1318 x 80ft.
N = 23 fs = 0.46 TSF
N = 35 qp = 35 TSF
Qs = 0.46 x (1.5 x 3.1416 x 80) =173 Ton
Qp = 35 x (1/4 x 3o1416 x 1o5 x 145) =62 Ton
Qa = Qs / 2.0 + Qp / 3.0 =173/2 + 62/3.0 = 86 + 31= 117 Ton > 80 Ton.
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6. Founding LevelFounding level should be determined by observing the soil type from the boring. Suitable founding soil should be weathered granite bedrock or oompacted/cemented clayey silt with gravels, or up to a max depth of eft'. In case of dou7gt, SPT should be carried in the bored base.
7. RecommendationUse 18 bored pile Vrith max capacity 80 Ton per pile. Site engineer should use the DB results to determine the founding level. Para 6 above can be used as a guide. 4 Nos load tests should be carried out to verify the capacity.
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Lampiran E 6
1. ObjectiveTo design the foundation system for the proposed Dewan Orang Ramai in Kampung Cheras Baru
2. Introduction2.1 The proposed.structure is a one-storey assembly-hall'situated on Lot 405 in
Kampung Ceras Baru, M11rim Ampang, Daerah Hulu Langat
2.2 Column loadsMaximum - 68TMinimum - 30T
3. Site Condition3.1 Surface Condition
The terrain is generally flat. It was formerly an old building site that has been cleared. Springs of water are visible which suggest the ground water table is very near the ground surface. The only visible form of undergrowth are bushes and shrubs.
3.2 Subsurface Condition3.2.1 Referring to the geological map of Kuala Lumpur District (after Ting
and Ooi 1972)2, Kampung Cheras Baru is located in the Granite region. Hence the soil is residual Gradite soil.
3.2.2 Scope of Site Investigation.Initially 6 Nos of JKR Probes were performed by the district office of JKR Hulu Langat. Due to the inconsistency of the probe results, a more elaborate method of sub-soil exploration in the form of 3 Nos. Deep Boring was done by the Unit Makmal Ibu Pejabat JKR. Borehole positions are as indicated in Appendix B. From the borelog results (APPENDIX C) the soil profile is not consistent along the threeboreholes. Generally) though, the sub-soil eonsists of interlayer between sand, clay and stilt. The first 9 metres Appears to be comprised of loose to medium dense sand and very soft-to firm clays (the variation occuring with depth). Below 9m the soil seems to improve from medium dense to very dense silts and sands as well as stiff to very hard clays. The groundwater is very near to the surface and the subsoil is assumed to be fully saturated.
3.2.3 Other Relevant Information.Near to the proposed site of the hall, in a north, easterly direction is situated a quarry. There is an access-road leading to the intended site but it is in a bad state.
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4. Foundation Analysis and Recommendation
4.1 Selection of type of foundationWith reference-to the results obtained from the S.I. done the first 5 metres comprises of compressible material which is of insufficient strength to sustain the intended imposed loads. Hence an ordinary shallow foundation in the form of a pad footing would not suffice. A piled foundation system is warranted here in order to transfer the loads to the stronger material found below 15m of the ground-level. In selecting the particular type of pile'to be used, particular consideration has been made to(a) Cost.
(b) Driving lengths
(c) Resistance to hard driving.
(d) Strength mf pile as structural member
(e) Effectiveness in mobilising friction and end-bearing
From Table 1, the most apparent' choice would be to use steel piles. However, based on the soil variation (profile) and the intended loading system which is relatively small, the .use of steel' piles is overly conservative. Furthermore hard driving is not expected.RC piles would be more appropriate in this case because; (a) it is more economical
(b) RC piles would be able to mobilise sufficient safe end-bearing resistance at a much shallower depth than would be necessary fdv its steel counterpart.
(c) Due to its rougher surface texture RC piles can mobilise frictional resistance better than steel piles
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(see Table 1)Table 1 : Selection of Pile TypeType
of pile
R.C. v 2 v 2 v 2 v 1 v 2 v 2
Steel v 1 v 1 v 1 v 2 v 1 X 3
Timber X 3 X 3 X 3 X 3 X 3 v 1
Figures in box represen