Design of Micropile GEOPROFOUND ENGINEERING SDN BHD
Pile Geotechnical Design using SPT Values
Site:
Round Pile f = 1000 mm 3.142
Skin Area per m, As= Base Area, Ab = 0.785 m
2
Factor of Safety (FoS) = 2.000
Unit End Bear at
Skin Skin Cumulative depth, End Bear at Pile Ultimate Pile Allowable Pile Capacity (kN)
Depth Avg SPT
Fric, fs Fric, Fs Skin Fric, Fs qb=min(400N/ depth, Qb Capacity, Qult = Capacity, Qall =
Interval (m) Value, N
= 2N (kN) (kN) 3, 10000) (kN) Fs+Qb (kN) Qult/FoS (kN)
0 2000 4000
(kN/m )
2
(kN/m2) 0
1 11 22 69.1 69.1 1466.7 1151.9 1221.0 610.5
2 11 22 69.1 138.2 1466.7 1151.9 1290.1 645.1
3 2 4 12.6 150.8 266.7 209.4 360.2 180.1
4 2 4 12.6 163.4 266.7 209.4 372.8 186.4 5
5 2 4 12.6 175.9 266.7 209.4 385.4 192.7
6 13 26 81.7 257.6 1733.3 1361.4 1619.0 809.5
7 26 52 163.4 421.0 3466.7 2722.7 3143.7 1571.8
8 21 42 131.9 552.9 2800.0 2199.1 2752.0 1376.0
10
9 21 42 131.9 684.9 2800.0 2199.1 2884.0 1442.0
10 1 2 6.3 691.2 133.3 104.7 795.9 397.9
11 12 24 75.4 766.5 1600.0 1256.6 2023.2 1011.6
Depth (m)
12 5 10 31.4 798.0 666.7 523.6 1321.6 660.8
15
13.5 6 12 56.5 854.5 800.0 628.3 1482.8 741.4
15 6 12 56.5 911.1 800.0 628.3 1539.4 769.7
16.5 1 2 9.4 920.5 133.3 104.7 1025.2 512.6
18 3 6 28.3 948.8 400.0 314.2 1262.9 631.5
19.5 1 2 9.4 958.2 133.3 104.7 1062.9 531.5 20
21 2 4 17.0 975.2 240.0 188.5 1163.6 581.8
23 2 4 22.6 997.8 240.0 188.5 1186.3 593.1
24 2 2464.8 7743.2 8741.0 10000.0 7854.0 16595.0 8297.5
25
Specified Working Load = 8000 kN Depth required = 13 m
30
(Based on given BH/MKT Report & above FoS)
11/24/2011
Design of Micropile GEOPROFOUND ENGINEERING SDN BHD (707134-T)
Micropile Structural Capacity Calculation
Pile Diameter, f = 1000 mm
Grade, fcu 35 cement grout (w/c ratio = 0.45)
Use API Pipe, f 88.9 mm 6.45 mm thk
2
fy = 500 N/mm (min)
Area of Steel & Concrete
As (provided) = 2prt
2
As = 1670.707 mm
Ac = p*d2/4
2
Ac = 785500 mm
Ultimate Axial Load,
fu = 0.4fcu*Ac + 0.75fy*As
fu = 11623515 N
fu = 11623.5151 kN
Taking Factor of Safety (FoS) = 2
fall = fu/FoS
fall = 5811.8 kN
Based on the structural capacity above, the micropile is able to take the given working load
of 5811.8 kN
Micropile Details
Micropile, Dia 1000 mm
API Pipe inside
f 88.9
6.45 mm thk
Clear spacing/Cover = 455.6 mm
Cement grout, G 35 N
W/C Ratio 0.45 min
11/24/2011
Design of Micropile GEOPROFOUND ENGINEERING SDN BHD (707134-T)
Micropile Structural Capacity Calculation
Pile Diameter, f = 1000 mm
Grade, fcu 35 cement grout (w/c ratio = 0.45)
Use Rebar, f 32 mm 25 Nos
2
fy = 460 N/mm (min)
Area of Steel & Concrete
As (provided) = Sprbars2
2
As = 20106.19 mm
Ac = p*d /4
2
2
Ac = 785500 mm
Ultimate Axial Load,
fu = 0.4fcu*Ac + 0.75fy*As
fu = 17933637 N
fu = 17933.6366 kN
Taking Factor of Safety (FoS) = 2
fall = fu/FoS
fall = 8966.8 kN
Based on the structural capacity above, the micropile is able to take the given working load
of 8966.8 kN
Micropile Details
Micropile, Dia 1000 mm
R6 Spiral Link
Rebar 4Y12
Cement grout, G 35 N
11/24/2011
Design of Micropile GEOPROFOUND ENGINEERING SDN BHD (707134-T)
W/C Ratio 0.45 min
11/24/2011