CAPACITY OF SUCTION CAISSON
1
CONTENTS
Objective What is suction caisson? Installation of suction caisson Why suction caisson? How to study? Results
2
CONTENTS
What is suction caisson? Installation of suction caisson Why suction caisson? How to study? Result
3
CONTENTS
WHAT IS SUCTION CAISSON?
Installation of suction caisson
W hy suction cais c aisso son? n?
How to study?
Result
4
WHAT IS SUCTION CAISSON?
Suction Caisson
“buckets”, “skirted foundations” and “suction anchors”
Upturned steel bucket install by suction of air or water out of the water cavity
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WHAT IS SUCTION CAISSON?
used in:
the oil and gas industry in the construction of platforms
now, looking forward for wind turbines foundation development
1st introduced by Senpere and Auvergne (1982) as mooring anchors for a storage tanker in the Gorm field located offshore Denmark.
6
CONTENTS
What is suction caisson?
INSTALLATION OF SUCTION CAISSON
Why suction caisson?
How to study?
Results
7
Installation of suction caisson
Launched from an installation vessel, landed softly on the sea floor
Lowered to the sea floor with the valves open so that the enclosed air can escape rapidly
Once the suction caisson has penetrated the sea floor under its own weight, the relief valves are closed
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Installation of suction caisson
Removing the trapped water from the suction caisson by means of pumps mounted on the top
Difference between the external hydrostatic water pressure and the inside of the suction caisson generates the driving force for soil penetration
Pumping is stopped after reaching the desired depth
Pumps are recovered for reuse elsewhere
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CONTENTS
What is suction caisson?
Installation of suction caisson
WHY SUCTION CAISSON?
How to study?
Results
10
WHY SUCTION CAISSON?
Most of the offshore foundation and structure used pile foundation instead of suction caisson.
Pile foundations for offshore platforms:
traditionally designed based on yield of an individual pile
require heavy duty piling equipment
time consuming and expensive
type is not suitable for locations with many large boulders in the seabed
Failure mechanism of piles
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Failure mechanism of piles
12
13
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WHY SUCTION CAISSON?
Suction caisson:
it is easy to install within one day at precise location
environmentally friendly
incur less decommissioning issues as it can be easily by reverse the direction of the pumping
lower cost
besides supporting platform, suction caisson can also be designed for storing oil during oil extraction.
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Contents
What is suction caisson? Installation of suction caisson Why suction caisson? Results
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CAPACITY OF SUCTION CAISSON VERTICAL LOADING
SAND
CLAY
SELFWEIGHT PENETRATION
HORIZONTAL LOADING
SAND
SUCTION ASSISSTED PENETRATION
CLAY
LIMIT TO SUCTION PENETRATION
UPLIFT LOADING
SAND
CLAY
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Loading Condition Acquire formula involved in the calculation
Acquire value of parameters involved
.
Formulate calculation file in Microsoft Excel
Substitute all the parameters into the formula.
Generate graph from the calculation to compare the behavior 18
CONTENTS
What is suction caisson?
Installation of suction caisson
Why suction caisson?
RESULTS
19
RESULT VERTICAL LOAD Self weight Penetration (Clay)
V ' h o su1 Do h i su1 Di
' hN q
su 2 N c Dt
16,000.00
14,000.00
12,000.00
) 10,000.00 N k ( d a o L 8,000.00 l a c i t r e V 6,000.00
4,000.00
2,000.00
0.00 0.00
2.00
4.00
Vertical Load versus Z/h in Clay
6.00 Z/h
8.00
10.00
12.00 20
RESULT VERTICAL LOAD Self weight Penetration (Clay)
V ' h o su1 Do h i su1 Di
' hN q
su 2 N c Dt
12,000.00
10,000.00
8,000.00
) N k ( d a o L 6,000.00 l a c i t r e V 4,000.00
2,000.00
0.00 0.00
2.00
4.00
Vertical Load versus Z/D in Clay
6.00 Z/D
8.00
10.00
12.00
21
RESULT VERTICAL LOAD Self weight Penetration (Sand) V '
' h2 2
K tan o Do
' h2 2
K tan i Di ' hN q '
t 2
N Dt
250,000.00
200,000.00
) N 150,000.00 k ( d a o L l a c i t r e 100,000.00 V
50,000.00
0.00 0.00
2.00
4.00
6.00
8.00
10.00
12.00 22
Vertical Load versus Z/h in Sand
Z/h
RESULT VERTICAL LOAD Self weight Penetration (Sand) V '
' h2 2
K tan o Do
' h2 2
K tan i Di ' hN q '
t
2
6.00
8.00
N Dt
100,000.00
90,000.00
80,000.00
70,000.00 ) N 60,000.00 k ( d a o L 50,000.00 l a c i t r e 40,000.00 V
30,000.00
20,000.00
10,000.00
0.00 0.00
2.00
4.00
10.00
12.00 23
RESULT VERTICAL LOAD Suction Assisted Penetration (Clay)
Do2 h o su1 Do h i su1 Di ' h su 2 N c Dt V ' s 4 14,000.00
12,000.00
10,000.00
) N k ( n o i t c 8,000.00 u S + d a o L 6,000.00 l a c i t r e V
4,000.00
2,000.00
0.00 0.00
2.00
4.00
6.00
8.00
10.00
12.00
24
RESULT VERTICAL LOAD Suction Assisted Penetration (Clay)
Do2 h o su1 Do h i su1 Di ' h su 2 N c Dt V ' s 4 10,000.00 9,000.00 8,000.00
) N k ( n o i t c u S + d a o L l a c i t r e V
7,000.00 6,000.00
5,000.00 4,000.00 3,000.00 2,000.00 1,000.00 0.00 0.00
2.00
4.00
Vertical Load versus Z/D in Clay
6.00 Z/D
8.00
10.00
12.00
25
RESULT VERTICAL LOAD Suction Assisted Penetration (Sand) h h Di2 as 2 h h 1 a s 2 ' Z o exp 1 K tan o Do ' Z o exp 1 K tan i Di h h 4 Z o Z o Z i Z i
V ' s
1 a s h Z i exp 1 N q ' tN } Dt ' h Z i 2,000,000.00
1,500,000.00
) N k ( n 1,000,000.00 o i t c u S + d a o L l a 500,000.00 c i t r e V
0.00 0.00
-500,000.00
2.00
4.00
6.00
8.00
10.00
12.00
26
RESULT VERTICAL LOAD Suction Assisted Penetration (Sand) h h Di2 as 2 h h 1 a s 2 ' Z o exp 1 K tan o Do ' Z o exp 1 K tan i Di h h 4 Z o Z o Z i Z i
V ' s
1 a s h Z i exp 1 N q ' tN } Dt ' h Z i 1,400,000.00
1,200,000.00
) N k ( n o i t c u S + d a o L l a c i t r e V
1,000,000.00
800,000.00
600,000.00
400,000.00
200,000.00
0.00 0.00
2.00
4.00
6.00
8.00
10.00
12.00
27
RESULT VERTICAL LOAD Limit to Penetration (Clay) Di2 Di2 ' h su 2 N c Dt h o su1 Do 1 2 V ' N su2 2 4 Dm Do * c
3,000.00
2,500.00
) N k ( 2,000.00 n o i t a r t e n e P 1,500.00 n o i t c u S o t t i 1,000.00 m i L
500.00
0.00 0.00
2.00
4.00
6.00
8.00
10.00
12.00
28
RESULT & FINDING VERTICAL LOAD Limit to Penetration (Clay) Di2 Di2 ' h su 2 N c Dt h o su1 Do 1 2 V ' N su2 2 4 Dm Do * c
1,800.00
1,600.00
1,400.00 ) N k 1,200.00 ( n o i t a r t e 1,000.00 n e P n o i 800.00 t c u S o t t i 600.00 m i L
400.00
200.00
0.00 0.00
2.00
4.00
6.00
8.00
10.00
12.00 29
RESULT VERTICAL LOAD Limit to Penetration (Sand) V '
' h Di2
'
h h 1 K tan n o Do Z o Z o
Z o exp
1 a4 1 a ' tN Dt
2
30,000.00
25,000.00
20,000.00
) N k ( n o i t c 15,000.00 u S o t t i m i L
10,000.00
5,000.00
0.00 0.00
2.00
4.00
Vertical Load versus Z/h in Sand
6.00
8.00
10.00
12.00
30
RESULT VERTICAL LOAD Limit to Penetration (Sand) V '
' h Di2
'
h h 1 K tan n o Do Z o Z o
Z o exp 2
1 a4 1 a ' tN Dt
16,000.00
14,000.00
12,000.00
) N 10,000.00 k ( n o i t c u 8,000.00 S o t t i m i 6,000.00 L
4,000.00
2,000.00
0.00 0.00
2.00
4.00
6.00
8.00
10.00
12.00
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RESULT HORIZONTAL LOAD (Clay)
H u N h As u ( 2
3
N h
L)
4
4
d d 6.3 L L
4
L 7.02 D
0.3785
1.58e
L 0.775 D
1,200.00
1,000.00
N k ( d a o L l a t n o z i r o H
800.00
600.00
400.00
200.00
0.00 -1.00
1.00
3.00
Horizontal Capacity versus L/d in Cl
5.00 L/d
7.00
9.00
11.00
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RESULT HORIZONTAL LOAD (Clay)
H u N h As u ( 2
3
N h
L)
4
4
d d 6.3 L L
4
L 7.02 D
0.3785
1.58e
L 0.775 D
1,400.00
1,200.00
1,000.00 ) N k ( d a o L l a t n o z i r o H
800.00
600.00
400.00
200.00
0.00 -1.00
1.00
3.00
Horizontal Capacity versus L/D in clay
5.00 L/D
7.00
9.00
11.00
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RESULT HORIZONTAL LOAD (Sand) 2d L
' DL3 tan2 450 Qu
2
20,000.00 18,000.00 16,000.00 14,000.00 N k ( d 12,000.00 a o L l 10,000.00 a t n o z i r 8,000.00 o H
6,000.00 4,000.00 2,000.00 0.00 0.00
2.00
4.00
6.00
8.00
10.00
12.00 34
L/d
RESULT HORIZONTAL LOAD (Sand) 2d L
' DL3 tan2 450 Qu
2
30,000.00
25,000.00
20,000.00 ) N k ( d a o L l 15,000.00 a t n o z i r o H
10,000.00
5,000.00
0.00 0.00
2.00
4.00
Horizontal Capacity versus L/D Sand
6.00 L/D
8.00
10.00
12.00
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RESULT UPLIFT LOAD (Clay)
V u pu A
pu N c Dc su (tip) ' L
L N c 8 D
0.1833
30,000.00
25,000.00
20,000.00 N k ( d a o L15,000.00 t f i l p U
10,000.00
5,000.00
0.00 0.00
2.00
4.00
6.00
8.00
10.00
12.00
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RESULT UPLIFT LOAD (Clay)
V u pu A
pu N c Dc su (tip) ' L
L N c 8 D
0.1833
30,000.00
25,000.00
20,000.00 N K ( d a o L15,000.00 t f i l p U
10,000.00
5,000.00
0.00 0.00
2.00
4.00
6.00
8.00
10.00
12.00
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RESULT UPLIFT LOAD (Sand)
V u pu A
pu (net )
L 9.1 D
0.5372
1 sin 'OCR0.5 tan ' v' (bottom)
350,000.00
300,000.00
250,000.00
) N k ( 200,000.00 d a o L t f i l 150,000.00 p U
100,000.00
50,000.00
0.00 0.00
2.00
4.00
Uplift Load versus L/d in Sand
6.00
8.00
10.00
12.00
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RESULT UPLIFT LOAD (Sand)
V u pu A
pu (net )
L 9.1 D
0.5372
1 sin 'OCR0.5 tan ' v' (bottom)
350,000.00
300,000.00
250,000.00 ) N k ( d 200,000.00 a o L l a t n o z 150,000.00 i r p H
100,000.00
50,000.00
0.00 0.00
2.00
4.00
6.00
Uplift Load versus L/D in Sand
L/D
8.00
10.00
12.00
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CONTENTS
Objective What is suction caisson? Installation of suction caisson Why suction caisson? How to study? Result
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