oca on : ro ec :
BORE PILES IN 0
-16
INPUT Depth Below GL or Chart Datum m 0 -0.5 -1 -3.5 -4 -7 -7.5 -9.5 -10 -11.5 -12 -14 -16 -18 -20 -22
av a
C Cohesion
Unconfined Compressive Strength
q
c
u
kg/cm2 0 1.2 1.2 1.2 1.2 1.2 1.2 1.2 1.2 1.2 1.2 1.2 1.2 1.2 1.2 1.2
u
kg/cm2 0 0.00 0.29 0.29 0.07 0.07 0.07 0.07 0.04 0.04 0.52 0.52 0.52 0.52 0.52 0.52
Soil Density
Drgree
kg/cm3 0 1.6 1.6 1.6 1.6 1.6 1.6 1.6 1.6 1.6 1.6 1.6 1.6 1.6 1.6 1.6
0 0 13 13 27 27 27 27 29 29 10 10 20 20 20 20
K
Coefficient of Earth Pressure Adhesion Factor Design Load
tonne
Pile Dia. In CM Factor of safety for Skin Friction Factor of safety for end bearing Factor of safety overall
cm
Qhg = Mg = qu 1.6
SOIL
Soil Properties For PY Cu 0.6
n
Φ
0
TYPICAL VALUES OF Soil Type Dry Loose Sand 0.26 Medium Sand 0.775 Dense Sand 2.076 Very loose sand under repeated loading Choose value of nh = 0.146 Ref. IS : 2911 (Part 1. Sec. 2) Concrete Mix M 35
1 h 100 75 2 2 2.5
tonne 50 tm 100 c=cohesive n=non-cohesive c
(kg/cm3) Submerged 0.146 0.526 1.245 0.041
VK BHAVADASAN
VK Bhavadasan
12th January 2004
12/8/2014
2
Depth vs Load
400
350
Ultimate Skin Friction Ultimate End Bearing 300
Total safe Load Total Design Load
250
d a o L
200
150
100
50
0 0
-0.5
-1
-3.5
-4
-7
-7.5
-9.5
-10
-11.5
-12
-14
-16
-18
-20
-22
Depth
SAFE AT -16
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VK Bhavadasan
12th January 2004
12/8/2014
Deph Of Pile 0 -0.5 -1 -3.5 -4 -7 -7.5 -9.5 -10 -11.5 -12 -14 -16 -18 -20 -22
VK Bhavadasan
Ultimate Skin Friction 0 0 6.136334 36.818 43.66894 84.77455 91.62549 119.0292 125.9719 146.7998 154.3783 184.6925 223.8492 263.0058 302.1625 341.3192
Ultimate End Bearing 0 0 12.16544 55.22248 52.79632 65.27971 65.27971 85.33399 85.51227 10.50969 29.61488 46.51619 46.51619 46.51619 46.51619 20.67561
Total safe Load 0 0 7.32071 36.81619 38.5861 60.0217 62.76208 81.74529 84.59365 62.92378 73.59728 92.48347 108.1461 123.8088 139.4715 144.7979
Design Load 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
12th January 2004
12/8/2014
Piles in Soil Intermediate Between Sand and Clay 3 1] When Piles are installed in SANDY CLAY, which are predominantly Cohesive in character the Skin friction and end bearing resistance should be calculated assuming 0 2] When Pile is installed in CLAYEY SAND where the Cohesion is relatively small, the carrying capacity shall be calculated assuming C = 0 3] In SANDY CLAY or SANDY SILTS and SILTY or CLAYEY SANDS, which possess appreciable cohesion C - Φ soil, and the ultimate capacity can be estimated using
and frictional components, can be termed as e uation below.
Q A q
p ult
up
C a K (tan a )d As
Granular Soil ULTIMATE POINT RESISTANCE (General Approach) The ultimate point resistance does not necessarly increase with depth, and vertical effective stress is not equal to the effective overburdon pressure but reaches a limiting value Zc. The ratio Zc/D , falling in the range of 5 to 20 is given in Fig. 03 There is a wide variation in the values recomented for Nq as showen in Fig. 05. Nq value established by Berezantsev (1961) confirm to practical criteria of Pile faliure. For values of Nq, the graph provided in IS 2911 is adopted which is based on Berezantsev's curve up to 35 degree and Vesic's curve beyond 35 degree, as shown in Fig. 04. ULTIMATE SKIN FRICTION The value of skin friction coefficient is influenced by many factors; including angle of internal friction, method of instalation, pile material, shape etc. For bore pile in which bore holes are stablised by bentonite this value K δ =
ma be estimated assumin
1
Cohesive Soil ULTIMATE POINT RESISTANCE (General Approach) The value of Nc used in the design is as that proposed by Skempton (1961). For circular area, the value increases from 6.14 to a limiting value of 9 for depths greater than 4 times diameter.The values are shown in table No. 01 PILE - SOIL ADHESION The pile - soil adhesion depends on various factors. For simplicity, Ca has been related to undrained cohesion Cu of soil. The ratio Ca / Cu is termed as adhesion factor. The adhesion factor is taken as shown in Figure No. 01.The Australian Code AS 2159 provides higher values of adhesion factor, while Dr.NV Nayak propose adhesion factor as 1 for bored cast in situ RCC piles in all clay of any consistency. Two values for adhesion factor are drawn in the graph. The lower value is as given in Ref. Book by Dr. NV Nayak, (p.No.166). The Higher values as per Australian Code. By entering "L" or "H" appropriate value for adhesion factor can be selected. LATERAL RESISTANCE - ELASTIC METHOD A vertical pile resist horizontal loads when reaction in the surrounding soil is moblised. The behaviour of soil in such loading condition depends on the relative stiffness of soil and the pile. Relative Stiffness, T is given by the formula T Where: E = Modulas of Elasticity of pile I = Moment of Inertia Nh = Unit Modulus of Subgrade Reaction
EI nh
1 5
3 2 Q M g T Deflection Y is given by the firmula y h g T A y EI B y EI
Moment =
Shear =
VK Bhavadasan
M M A
B
V V V A
B
B Q T A M m
hg
g
m
Q A M B g
hg
V
T
V
12th January 2004
12/8/2014
Soil Reaction =
X X
X
Y
Y
L
Y
+
=
Output Safe load at various depths Depth Ultimate Ultimate Skin End Friction Bearing
5
4
Qhg M g p p A p B T A p T 2 B p
Ultimate Pile Capacity
Safe Load
0 -0.5 -1 -3.5 -4 -7
0 0.00 6.14 36.82 43.67 84.77
0 0.00 12.17 55.22 52.80 65.28
0 0.00 18.30 92.04 96.47 150.05
0 0.00 7.32 36.82 38.59 60.02
-7.5 -9.5 -10 -11.5 -12 -14 -16 -18 -20 -22
91.63 119.03 125.97 146.80 154.38 184.69 223.85 263.01 302.16 341.32
65.28 85.33 85.51 10.51 29.61 46.52 46.52 46.52 46.52 20.68
156.91 204.36 211.48 157.31 183.99 231.21 270.37 309.52 348.68 361.99
62.76 81.75 84.59 62.92 73.60 92.48 108.15 123.81 139.47 144.80
EI / kh
EI
L
5xT
1.60
41935.20
16.00
7.99
Design Load 100
Pile Diimetre 75
Pile is a long elastic pile,Reese and M atlock method is applicable
Ref: 1 FOUNDATION DESIGN MANUAL By Dr.Narayan V Nayak 2 ANALYSIS AND DESIGN OF FOUNDATIONS AND RETAINING STRUCTURES By Dr. Shamsher Prakesh
VK Bhavadasan
12th January 2004
12/8/2014
5 Fig. 01
ADHESION FACTOR 1.20 1.00 r o t c 0.80 a F n 0.60 o i s e h d 0.40 A
0.20 0.00 0.0
0.5
1.0
1.5
2.0
2.5
Cohesion kg/cm2
Adhesion Factor
Adhesion Factor as per Australian Code Fig. 02 Nc
10 9 8 7 6 5
Table 01
Nc
4
Cohesive Soils End-bearing L/d Nc 0 6.14 1 7.6 2 8.3 3 8.8 4 9
3 2 1 0 1
2
3
4
5
Fig. 03 Critical Depth
25 20 15 D / z
10 5 0 25
VK Bhavadasan
30
35 Angle
12th January 2004
40
45
12/8/2014
Fig. 04
6
BEARING CAPACITY FACTOR - Nq
1000.00
100.00
q N
10.00
1.00 1 2 3 4 5 6 7 8 9 101112131415161718192021222324252627282930313233343536373839404142434445 Angle of internal friction
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VK Bhavadasan
12th January 2004
12/8/2014
7 Fig. 05
VK Bhavadasan
12th January 2004
12/8/2014
T m 1.60 Z 0 -0.1 -0.2 -0.3 -0.4 -0.5 -0.6
Qhg t 50.00 M t-m 100 108 116 123 129 134 138
Mg t-m 100.00 Length m 0 -0.160 -0.319 -0.479 -0.639 -0.799 -0.958
-0.7 -0.8 -0.9 -1
141 143 144 143
-1.118 -1.278 -1.438 -1.597
-1.2 -1.4 -1.6 -1.8 -2 -3 -4 -5
139 130 119 105 91 24 -4 -5
-1.917 -2.236 -2.556 -2.875 -3.195 -4.792 -6.390 -7.987
T m 1.60 Z 0
Qhg t 50.00 V t 113
Mg t-m 100.00 Length m 0
-0.1 -0.2 -0.3 -0.4 -0.5 -0.6 -0.7 -0.8 -0.9 -1 -1.2 -1.4 -1.6 -1.8 -2 -3 -4 -5
112 110 108 104 99 94 88 82 75 68 54 40 28 16 7 -14 -8 -1
-0.160 -0.319 -0.479 -0.639 -0.799 -0.958 -1.118 -1.278 -1.438 -1.597 -1.917 -2.236 -2.556 -2.875 -3.195 -4.792 -6.390 -7.987
VK Bhavadasan
8 Depth vs Moment
Am
Bm
0 -50
0
50
-1 -2 -3 m h t p e D
-4 -5 -6
0 100 0.1 0.198 0.291 0.379 0.459 0.532
1 150 1 0.999 0.994 0.987 0.976 0.96
0.595 0.649 0.693 0.727
0.939 0.914 0.885 0.852
0.767 0.772 0.746 0.696 0.628 0.225 0 Moment - t-m -0.033
-7 -8 -9
200
0.775 0.688 0.594 0.498 0.404 0.059 -0.042 -0.026
Depth vs Shear Force
Av
0 -50
-1
0
-2 -3 m h t p e D
-4 -5 -6 -7 -8 -9
12th January 2004
1 50
Bv 1
100
150
0.989 1 0.956 0.999 0.906 0.994 0.84 0.987 0.764 0.976 0.677 0.96 0.585 0.939 0.489 0.914 0.392 0.885 0.295 0.852 0.109 0.775 -0.056 0.688 -0.193 0.594 -0.298 0.498 -0.371 0.404 -0.349 0.059 Shear Force - t-0.042 -0.106 0.013 -0.026
12/8/2014
T m 1.60
Qhg t 50.00
Mg t-m 100.00
Z
Y
0 -0.1 -0.2 -0.3 -0.4 -0.5
mm 2.17 1.99 1.81 1.64 1.48 1.33
Legth m 0 -0.159738702 -0.319477403 -0.479216105 -0.638954806 -0.798693508
-0.6 -0.7 -0.8 -0.9
1.18 1.05 0.92 0.80
-0.958432209 -1.118170911 -1.277909612 -1.437648314
-1 -1.2 -1.4 -1.6 -1.8 -2 -3 -4 -5
0.69 0.49 0.33 0.20 0.10 0.03 -0.09 -0.04 0.00
-1.597387015 -1.916864418 -2.236341821 -2.555819224 -2.875296627 -3.19477403 -4.792161045 -6.38954806 -7.986935075
T m 1.60
Qhg t 50.00
Mg t-m 100.00
Z
P
Legth
0 -0.1 -0.2 -0.3 -0.4 -0.5 -0.6 -0.7 -0.8 -0.9 -1 -1.2 -1.4 -1.6 -1.8 -2 -3 -4 -5
t/m 0 -12.78796192 -23.35938564 -31.78476268 -38.18955353 -42.81653385 -45.75197373 -47.23864884 -47.38624111 -46.37492398 -44.37698159 -38.20451704 -29.97304392 -20.90432989 -11.81271604 -3.371560438 17.57708005 9.748911731 1.361470643
m 0 -0.159738702 -0.319477403 -0.479216105 -0.638954806 -0.798693508 -0.958432209 -1.118170911 -1.277909612 -1.437648314 -1.597387015 -1.916864418 -2.236341821 -2.555819224 -2.875296627 -3.19477403 -4.792161045 -6.38954806 -7.986935075
VK Bhavadasan
EI t-m4 41935.20
9
Depth vs Deflection Ay By
-0.50
0 0.00 -1 -2 -3
m h t p e D
2.435 2.273 0.50 2.112 1.952 1.796 1.644 1.496 1.353 1.216 1.086
-4 -5
1.623 1.453 1.50 1.00 1.293 1.143 1.003 0.873
2.00
2.50
0.752 0.642 0.54 0.448
0.962 0.364 0.738 0.223 0.544 0.112 0.381 0.029 0.247 -0.03 0.142 -0.07 -0.075 -0.089 -0.05 Deflection -0.028 - mm -0.009 0
-6 -7 -8 -9
EI t-m2 41935.19979 Ap
Bp
Depth vs Soil Reaction
-60
m h t p e D
0 0 0 -0.1450 -40 -0.227 -20 -0.422 -0.259 -1 -0.586 -0.343 -2 -0.718 -0.401 -0.822 -0.436 -3 -0.897 -0.451 -0.947 -0.449 -4 -0.973 -0.432 -0.977 -0.403 -5 -0.962 -0.364 -0.885 -0.268 -6 -0.761 -0.157 -7 -0.609 -0.047 -0.445 0.054 -8 -0.283 0.14 0.226 0.268 -9 0.1855 0.1006 Soil Reaction - t/m 0.046 -0.002
12th January 2004
20
40
12/8/2014
1 Base diam Shape
h 75 r
mm Depth
Pile Dia
Adhesion Factor 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75
Depth 0 -0.5 -1 -3.5 -4 -7 -7.5 -9.5 -10 -11.5 -12 -14 -16 -18 -20 -22
1 1 1 1 1 1 1 1 1 0.898 0.898 0.898 0.898 0.898 0.898
h
H
r=round s=square l Depth Incriment
Cu 0 0 0.29 0.29 0.072 0.072 0.072 0.072 0.035 0.035 0.52 0.52 0.52 0.52 0.52 0.52
0.5 0.5 2.5 0.5 3 0.5 2 0.5 1.5 0.5 2 2 2 2 2
a
C As
0.000 3.416 17.082 0.848 5.089 0.848 3.393 0.412 1.237 5.501 22.005 22.005 22.005 22.005 22.005
Skin Friction tan phi
Kd 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
0.0000 0.2309 0.2309 0.5095 0.5095 0.5095 0.5095 0.5543 0.5543 0.1763 0.1763 0.3640 0.3640 0.3640 0.3640
VERTICAL PILES SUBJECTED TO LATERAL FORCES Reese and Matlock's method DIAMETE m 0.75 Pile section r Relative stiffness T = For Cohesive Soil, T =
For Granular Soil, T =
5
5
cm 75.00
4
cm 1553156
2
m 0.441786
4
2 EI kn-m 419352
Length 16.00
nh
EI 4.19352E+11
1.597387015
z
(Terazagi 1956)
D
D,,
kh =
0.292
c EI
kh = T
0.536 T
5xT
m 2.391568
m 1.60
m 7.986935075
4
t-m 41935.2
E = modulus of elasticity = 5000 (fck)
cm 1553156
where, kh =
EI / kh
4
Moment of Inertia
M 35 E 35892.24192 29910.2016 5 EI / nh EI where, kh = 67 xCu /D (Terazagi 195 55746234666 EI / kh kh = 0.536 T
Assuming Fixity at For Soil Type Dia/Width I
Area
test sample calc
5
2
E = 2.7 x 10kg/cm (IS-456-2000) 270000 Pile is a long elastic pile,Reese and Matlock method is applicable Shaft Adhesion
su 0 10 20
1 1 1
cu 0 0.1 0.2
30 40 50
1 1 0.912
0.3 0.4 0.5
VK Bhavadasan
Adhesion or as per A 1 1 1.00 1.00 0.97 1.00 0.86 0.74 0.65
1.00 1.00 0.898
0 1 2 3
0.00 5 5 5
0.00 1.09 1.20 1.31
4 5 6
5 5 5
1.43 1.57 1.72
12/8/2014
60 0.783 0.6 70 0.702 0.7 80 0.621 0.8 90 0.564 0.9 100 0.516 1.0 110 0.477 1.1 120 0.443 1.2 130 0.413 1.3 140 0.388 1.4 150 0.37 1.5 160 0.354 1.6 170 0.339 1.7 180 0.33 1.8 190 0.321 1.9 200 0.319 2.0 Australian code recomends Better Adhesoin Factor
VK Bhavadasan
0.57 0.49 0.42 0.37 0.33 0.31 0.30 0.30 0.30 0.30 0.3 0.30 0.30 0.30 0.30
0.783 0.702 0.621 0.564 0.516 0.477 0.443 0.413 0.388 0.37 0.354 0.339 0.33 0.321 0.319
7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45
5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5.1 5.23 5.41 5.62 5.83 6.2 6.5 7 8 9.5 12 15 18 20 20 20 20
1.89 2.09 2.31 2.53 2.82 3.11 3.44 3.83 4.20 4.69 5.26 5.87 6.58 7.31 8.22 9.31 10.57 11.91 13.48 15.42 17.66 20.23 23.33 26.79 31.05 35.73 41.21 47.86 55.46 64.57 75.16 87.90 101.62 120.78 145.88 181.97 228.56 295.00 380.20
12/8/2014
Skin Friction
Total Ultimate Skin Friction 0 0.00 6.14 36.82 43.67 84.77 91.63 119.03 125.97 146.80 154.38 184.69 223.85 263.01 302.16 341.32
0.000 2.720 13.599 6.003 36.016 6.003 24.011 6.530 19.591 2.077 8.309 17.152 17.152 17.152 17.152
Safe Skin Friction
L/D
Nc
CNc
0 3.068167 18.409 21.83447 42.38727 45.81274 59.51461 62.98593 73.39988 77.18915 92.34625 111.9246 131.5029 151.0812 170.6596
0.666667 1.333333 4.666667 5.333333 9.333333 10 12.66667 13.33333 15.33333 16 18.66667 21.33333 24 26.66667 29.33333
6.14 7.6 9 9 9 9 9 9 9 9 9 9 9 9 9
0.00 9.74 11.53 2.86 2.86 2.86 2.86 1.39 1.39 20.68 20.68 20.68 20.68 20.68 20.68
c=cohesive n=non-cohesive
c design load 100
depth
L
-16
16
Qhg = Mg =
50 100
Soil Properties For PY qu 1.6
Cu 0.6
TYPICAL VALUES O Soil Type Loose Sand Medium Sand
Φ
0
n Dry
(kg/cm3) Submerged
0.26 0.775
0.146 0.526
Dense Sand 2.076 1.245 Very loose sand under repeated l 0.041 Choose value of nh = 0.146 Ref. IS : 2911 (Part 1. Sec. 2) Cohesive Soils End-bearing 10 qe=9Cu if L/d>4 8 qe=NcCu if L/d<=4 6 Table 01 L/d Nc 4
VK Bhavadasan
Depth -22 -20 -18 -16 -14 -12 -11.5
Depth
0 -0.5 -1 -3.5 -4 -7 -7.5 -9.5 -10 -11.5 -12 -14 -16 -18 -20 -22
Depth
Cumilative Depth
Critical Depth Z/D
0.5 1 3.5 4 7 7.5 9.5 10 11.5 12 14 16 18 20 22
0.0001 5 5 5 5 5 5 5.1 5.1 5 5 5 5 5 5
llowable Loa esign Loa 22 145 100 20 18 16 14 12 11.5
139 124 108 92 74 63
100 100 100 100 100 100
-10
10
85
100
-9.5 -7.5 -7 -4
9.5 7.5 7 4
82 63 60 39
100 100 100 100
-3.5 -1 -0.5 0
3.5 1
37 7
100 100
0.5 0
0 0
100 100
-16 SAFE AT
Nc
12/8/2014
2 0
0 1 2 31 4
6.14 7.6 8.3 2 8.8 9
3
4
5
400.00
350.00
300.00
250.00
200.00
150.00
100.00
50.00
0.00 1
VK Bhavadasan
5
9 13 17 21 25 29 33 37 41 45
12/8/2014
Density
Nq
QNq
h
0 1.6 1.6 1.6 1.6 1.6 1.6 1.6 1.6 1.6 1.6 1.6 1.6 1.6 1.6 1.6
0.0001 1 3.5 4 5 5 5 5.1 5.1 5 5 5 5 5 5
0.001 3.436 3.436 17.660 17.660 17.660 17.660 23.335 23.335 2.529 2.529 7.311 7.311 7.311 7.311
0.00 2.43 43.69 49.93 62.42 62.42 82.47 84.12 9.12 8.94 25.84 25.84 25.84 25.84 0.00
Ultimate End Bearing
0 0.00 12.17 55.22 52.80 65.28 65.28 85.33 85.51 10.51 29.61 46.52 46.52 46.52 46.52 20.68
Deph Of Pile 0 -0.5 -1 -3.5 -4 -7 -7.5 -9.5 -10 -11.5 -12 -14 -16 -18 -20 -22
Ultimate Skin Friction 0 0.000 6.136 36.818 43.669 84.775 91.625 119.029 125.972 146.800 154.378 184.692 223.849 263.006 302.162 341.319
Ultimate End Bearing 0 0.000 12.165 55.222 52.796 65.280 65.280 85.334 85.512 10.510 29.615 46.516 46.516 46.516 46.516 20.676
No of pile 1 1 1 1 2 2 2 2 2 2 2 3 3 14 _ _ 1 1
VK Bhavadasan
12/8/2014
VK Bhavadasan
12/8/2014
Total safe Load 0 0 7.32071 36.81619 38.5861 60.0217 62.76208 81.74529 84.59365 62.92378 73.59728 92.48347 108.1461 123.8088 139.4715 144.7979
VK Bhavadasan
Design Load 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
Safe End Bearing 0 7.32071 36.81619 38.5861 60.0217 62.76208 81.74529 84.59365 62.92378 73.59728 92.48347 108.1461 123.8088 139.4715 144.7979
0 0 6.082721 27.61124 26.39816 32.63985 32.63985 42.667 42.75613 5.254845 14.80744 23.2581 23.2581 23.2581 23.2581 10.3378
Total Pile Capacity 0 0 9.150888 46.02024 48.23263 75.02713 78.4526 102.1816 105.7421 78.65473 91.9966 115.6043 135.1827 154.761 174.3393 180.9974
12/8/2014
