Stability study of C-0172 - ODNZKG,4275388,/B17… · Stability study of C-0172 FEA and stability...
Transcript of Stability study of C-0172 - ODNZKG,4275388,/B17… · Stability study of C-0172 FEA and stability...
Reference 30147 Revision nr. 7 Date 14-12-2016 Subject C-0172 Page(s) 1/39
Stability study of C-0172
FEA and stability calculations
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Table of contents
Table of contents ........................................................................................................................................... 2
Samenvatting ................................................................................................................................................. 4
Introduction ................................................................................................................................................... 5
1. Technical Details of C-0172 ....................................................................................................................... 5
2. FEA Calculation for Jacking Purposes ......................................................................................................... 6
2.1. Results ................................................................................................................................................. 6
3. Stability Calculation .................................................................................................................................. 9
3.1. Annular ring ......................................................................................................................................... 9
3.2. 1st Shell course: Operating .................................................................................................................. 10
3.3. 1st Shell course: Test ........................................................................................................................... 11
3.4. 2nd Shell course: Operating ................................................................................................................. 12
3.5. 2nd Shell course: Test .......................................................................................................................... 13
3.6. 3rd Shell course: Operating .................................................................................................................. 14
3.7. 3rd Shell course: Test ........................................................................................................................... 15
3.8. 4th Shell course: Operating .................................................................................................................. 16
3.9. 4th Shell course: Test ........................................................................................................................... 17
3.10. 5th Shell course: Operating .................................................................................................................. 18
3.11. 5th Shell course: Test ........................................................................................................................... 19
3.12. 6th Shell course: Operating .................................................................................................................. 20
3.13. 6th Shell course: Test ........................................................................................................................... 21
3.14. 7th Shell course: Operating .................................................................................................................. 22
3.15. 7th Shell course: Test ........................................................................................................................... 23
3.16. Primary Wind Girder ........................................................................................................................... 24
3.17. Secondary stiffening ring .................................................................................................................... 25
3.18. Overturning moment .......................................................................................................................... 26
3.19. Restistance to overturning .................................................................................................................. 27
3.20. Conclusion .......................................................................................................................................... 28
4. Aluminium Dome Load............................................................................................................................ 29
4.1. Dome details ...................................................................................................................................... 29
4.2. Dome Load Analysis ............................................................................................................................ 29
4.2.1. Model setup .................................................................................................................................. 29
4.3. Result ................................................................................................................................................. 29
5. Conclusion .............................................................................................................................................. 30
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A. FEM calculations dome load in shell ........................................................................................................ 31
A.1.1 Model properties ................................................................................................................................ 31
A.1.2 Units ................................................................................................................................................... 31
A.1.3 Material Properties ............................................................................................................................. 32
A.1.4 Loads and Fixtures ............................................................................................................................... 33
A.2 Mesh...................................................................................................................................................... 35
A.2.1 Mesh details ........................................................................................................................................ 35
A.2.3 Mesh control ....................................................................................................................................... 36
A.3 Results ................................................................................................................................................... 37
A.3.1 Stresses ............................................................................................................................................... 37
A.3.1 Displacement ...................................................................................................................................... 38
A.3.1 Equivalent strain ................................................................................................................................. 39
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Samenvatting
Tank C0172 is gecontroleerd op stabiliteit (gemeten wanddikte vergeleken met wanddikte als vereist volgens de norm). Daarbij zijn de volgende normen gebruikt als basis:
EEMUA159 Hierbij is voor de operationele condities (vulhoogte 15.6 meter met gas olie) rekening gehouden met 80% van de yield strength en 80% van de yield strength voor de test condities (vulhoogte 15.6 meter met water).
Omschrijving Gemeten (gemiddelde) dikte (mm)
Vereiste wanddikte
Operationele condities Test condities
EEMUA159 EEMUA159
1e ring 12.2 9.26 11.09
2e ring 9.4 7.77 9.30
3e ring 9.5 6.27 7.51
4e ring 7.8 4.78 5.72
5e ring 7.9 4.96 5.94
6e ring 7.2 2.71 3.24
7e ring 7.0 0.45 0.54
Omschrijving Voldoet?
Operationele condities Test condities
EEMUA159 EEMUA159
1e ring Ja Ja
2e ring Ja Ja
3e ring Ja Ja
4e ring Ja Ja
5e ring Ja Ja
6e ring Ja Ja
7e ring Ja Ja
Alle gemeten ringen voldoen voor zowel de operationele conditities (gas olie) als de test condities (water) aan de gestelde norm (EEMUA159, 80% van de yield strength) voor een vulhoogte van 15.6 meter. Eén extra verstijvingsring moet op de tank geplaatst worden, rekening houdend met een windsnelheid van 46.5 m/s. Voor de belasting als gevolg van vijzelen van de tank is een FEM analyse uitgevoerd. De maximale spanning die uit deze analyse volgt is 54 N/mm2 ter plaatse van de verbinding tussen de annulaire ring en de eerste tank ring. De maximaal toelatbare spanning (80% of de yield strength van 355 N/mm2 = 288 N/mm2) is een fator 5 hoger. Verder is ook een FEM analyse uitgevoerd met de belasting van het nieuw te plaatsen aluminium dak op de tank wand, wat resulteert in een spanning van 113 N/mm2.
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Introduction
Tank C0172 has been selected for renovation, the renovation included the following:
- Removal of the current floating roof
- Removal of the current floor plates, excluding the annular ring
- Jacking up of the tank to perform foundation repair
- Installing a new tank floor “coned down”
- Installing an aluminium domed roof
- Installing an IFR, at a later stage.
A survey report was performed on the tank on the 10th March 2016, by the company Rosen. The contents of the report form the basis of any hereafter following calculations.
Seeing a change of service is envisage for the tank, age of the tank and the results of the Rosen survey report, it has been decided to perform a few calculations on the tank in question.
Calculations to be performed:
- FEA calculation to see if the tank can withstand jacking
- Stability calculation according to the EEMUA159, manual calculation in excel
- FEA calculation to see if the tank can withstand the additional stress of the aluminum domed roof.
1. Technical Details of C-0172
Diameter : 42 mtr Tank total height : 15.93 mtr Filling height : Currently 15.8 mtr Last known medium : Gasoil
- Specific gravity : 0.835 kg/ltr Shell courses : 7 Materials used
- Annular ring : Ste 36 = DH 36 - 1st to 4th shell course : Ste 36 = DH 36 - 5th to 7th shell course : Ste 37-2 = S235JR
Top angle : Angle 85x67x6.9mm Wind speed used in calculations : 46.5 m/s Location primary girder : 1100 mm below the top of the tank Tubelures and tank penetrations : Not included in any calculation, assumed OK Summation of the Rosen Report
Description Height (m) Average Thickness (mm) Material : Assumed
Annular ring n/a 9.1 Ste 36
1st shell course 2.46 12.8 Ste 36
2nd shell course 2.47 10.2 Ste 36
3rd shell course 2.47 10.1 Ste 36
4th shell course 2.47 7.8 Ste 36
5th shell course 2.47 8 Ste 37-2
6th shell course 2.47 7.1 Ste 37-2
7th shell course 1.12 6.8 Ste 37-2
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2. FEA Calculation for Jacking Purposes
36 Jacking brackets are to be welded to the first shell course of the tank, in order to lift it so that the foundation repair can take place. Prior to jacking, the following will already have been done:
- The existing floor plates will have been removed - The current floating roof will have been removed
Fixed points used:
- The cross bars of the jacking brackets, 36x Loading
- Own weight of the tank, by means of std gravity.
2.1. Results
Mesh:
In order to perform a FEA calculation a so-called mesh is needed, this “cuts” the entire model into small pieces, these small pieces form the basis of the calculation
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Jacking brackets and fixed points (36x) in the circumference:
The cross bar, purple, is used as the fixed points for the calculation
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Stress Results:
A maximum stress of 54 N/mm2 is found at the junction of the annular ring and the 1st shell course. Conclusion: Seeing that the allowable stress in the material for jacking purposes is 0.8 x Re value of the material used/ in our case the Re value is 355 N/mm2 0.8 x 355 = 284 N/mm2 This value is decidedly larger than the resulting stress from the FEA calculation Is can be safely assumed that no adverse effects will occur when jacking the tank.
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3. Stability Calculation
The stability calculation is performed according to the EEMUA159, whereby: - 80% of the material Re is allowed during operating conditions and 80% during the test conditions.
For the operating conditions the specific gravity of gasoil was used to perform the calculation, this being 0.835 kg/ltr. Corrosion allowance for the design conditions is set at 0mm.
3.1. Annular ring
EEMUA159 : Annular Ring Calculation
Given / Assumed
Thickness 1st Shell Course 12.8 mm e1
- excl CA
Average thickness annular ring 9.1 mm
Calculation
A
ea = 3.0 + (e1/3)
= 7.27 mm GOVERNING
B
ea = 6 mm as a minimum
NOT GOVERNING
Notes
In the Rosen Report (Appendix A4) the average thickness of the
annular ring was measured as 9.1 mm.
The Annular ring is thus OK
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3.2. 1st Shell course: Operating
EEMUA159 : 1st Shell Course Calculation : Design Conditions
Given / Assumed
Symbol
Outside Diameter Tank 42 mtr D
Average thickness shell plate 12.8 mm
Shell height 2.46 mtr
Liquid Height 15.6 mtr Hc
Yield Strength 355 N/mm2 Ste 36 Re
Corrossion Allowance 0 mm c
Design pressure 10 mbar p
Used in calculation 0 0 if 10 mbar or less
Medium Gasoil
Specific gravity medium 0.835 kg/l W
Calculation : Shell Course Thickness
ec = (D/20.S).(98.W.(Hc-0.3)+p) + c
EEMUA159
0.80 x Re
Allowable Material Stress = 284 N/mm2 S
ec = 9.26 mm
Result
Actual average plate thickness 12.8 mm
EEMUA159
0.80 x Re
Required plate thickness incl CA 9.26 mm
SUFFICIENT
NON GOVERNING
Comments
Ste 36 is equivalent to GH36 and has a Re value of 355 N/mm2
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3.3. 1st Shell course: Test
EEMUA159 : 1st Shell Course Calculation : Test Conditions
Given / Assumed
Symbol
Outside Diameter Tank 42 mtr D
Average thickness shell plate 12.2 mm
Shell height 2.46 mtr
Liquid Height 15.6 mtr Hc
Yield Strength 355 N/mm2 Ste 36 Re
Design pressure 0 mbar 1.1 x p = pt
0 if 10 mbar or less
Medium Water
Specific gravity medium 1 kg/l W
Calculation : Shell Course Thickness
et = (D/20.S).(98.W.(Hc-0.3)+p) + c
EEMUA159
0.80 x Re
Allowable Material Stress = 284 N/mm2 S
et = 11.09 mm
Result
Actual average plate thickness 12.8 mm
EEMUA159
0.80 x Re
Required plate thickness incl CA 11.09 mm
SUFFICIENT
GOVERNING
Comments
Ste 36 is equivalent to GH36 and has a Re value of 355 N/mm2
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3.4. 2nd Shell course: Operating
EEMUA159 : 2nd Shell Course Calculation : Design Conditions
Given / Assumed
Symbol
Outside Diameter Tank 42 mtr D
Average thickness shell plate 10.2 mm
Shell height 2.47 mtr
Liquid Height 13.14 mtr Hc
Yield Strength 355 N/mm2 Ste 36 Re
Corrossion Allowance 0 mm c
Design pressure 10 mbar p
Used in calculation 0 0 if 10 mbar or less
Medium Gasoil
Specific gravity medium 0.835 kg/l W
Calculation : Shell Course Thickness
ec = (D/20.S).(98.W.(Hc-0.3)+p) + c
EEMUA159
0.80 x Re
Allowable Material Stress = 284 N/mm2 S
ec = 7.77 mm
Result
Actual average plate thickness 10.2 mm
EEMUA159
0.80 x Re
Required plate thickness incl CA 7.77 mm
SUFFICIENT
NON GOVERNING
Comments
Ste 36 is equivalent to GH36 and has a Re value of 355 N/mm2
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3.5. 2nd Shell course: Test
EEMUA159 : 2nd Shell Course Calculation : Test Conditions
Given / Assumed
Symbol
Outside Diameter Tank 42 mtr D
Average thickness shell plate 10.2 mm
Shell height 2.47 mtr
Liquid Height 13.14 mtr Hc
Yield Strength 355 N/mm2 Ste 36 Re
Design pressure 0 mbar 1.1 x p = pt
0 if 10 mbar or less
Medium Water
Specific gravity medium 1 kg/l W
Calculation : Shell Course Thickness
et = (D/20.S).(98.W.(Hc-0.3)+p) + c
EEMUA159
0.80 x Re
Allowable Material Stress = 284 N/mm2 S
et = 9.30 mm
Result
Actual average plate thickness 01.2 mm
EEMUA159
0.80 x Re
Required plate thickness incl CA 9.30 mm
NOT SUFFICIENT
GOVERNING
Comments
Ste 36 is equivalent to GH36 and has a Re value of 355 N/mm2
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3.6. 3rd Shell course: Operating
EEMUA159 : 3rd Shell Course Calculation : Design Conditions
Given / Assumed
Symbol
Outside Diameter Tank 42 mtr D
Average thickness shell plate 10.1 mm
Shell height 2.47 mtr
Liquid Height 10.67 mtr Hc
Yield Strength 355 N/mm2 Ste 36 Re
Corrossion Allowance 0 mm c
Design pressure 10 mbar p
Used in calculation 0 0 if 10 mbar or less
Medium Gasoil
Specific gravity medium 0.835 kg/l W
Calculation : Shell Course Thickness
ec = (D/20.S).(98.W.(Hc-0.3)+p) + c
EEMUA159
0.80 x Re
Allowable Material Stress = 284 N/mm2 S
ec = 6.27 mm
Result
Actual average plate thickness 10.1 mm
EEMUA159
0.80 x Re
Required plate thickness incl CA 6.27 mm
SUFFICIENT
NON GOVERNING
Comments
Ste 36 is equivalent to GH36 and has a Re value of 355 N/mm2
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3.7. 3rd Shell course: Test
EEMUA159 : 3rd Shell Course Calculation : Test Conditions
Given / Assumed
Symbol
Outside Diameter Tank 42 mtr D
Average thickness shell plate 10.1 mm
Shell height 2.47 mtr
Liquid Height 10.67 mtr Hc
Yield Strength 355 N/mm2 Ste 36 Re
Design pressure 0 mbar 1.1 x p = pt
0 if 10 mbar or less
Medium Water
Specific gravity medium 1 kg/l W
Calculation : Shell Course Thickness
et = (D/20.S).(98.W.(Hc-0.3)+p) + c
EEMUA159
0.80 x Re
Allowable Material Stress = 284 N/mm2 S
et = 7.51 mm
Result
Actual average plate thickness 10.1 mm
EEMUA159
0.80 x Re
Required plate thickness incl CA 7.51 mm
SUFFICIENT
GOVERNING
Comments
Ste 36 is equivalent to GH36 and has a Re value of 355 N/mm2
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3.8. 4th Shell course: Operating
EEMUA159 : 4th Shell Course Calculation : Design Conditions
Given / Assumed
Symbol
Outside Diameter Tank 42 mtr D
Average thickness shell plate 7.8 mm
Shell height 2.47 mtr
Liquid Height 8.2 mtr Hc
Yield Strength 355 N/mm2 Ste 36 Re
Corrossion Allowance 0 mm c
Design pressure 10 mbar p
Used in calculation 0 0 if 10 mbar or less
Medium Gasoil
Specific gravity medium 0.835 kg/l W
Calculation : Shell Course Thickness
ec = (D/20.S).(98.W.(Hc-0.3)+p) + c
EEMUA159
0.80 x Re
Allowable Material Stress = 284 N/mm2 S
ec = 4.78 mm
Result
Actual average plate thickness 7.8 mm
EEMUA159
0.80 x Re
Required plate thickness incl CA 4.78 mm
SUFFICIENT
NON GOVERNING
Comments
Ste 36 is equivalent to GH36 and has a Re value of 355 N/mm2
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3.9. 4th Shell course: Test
EEMUA159 : 4th Shell Course Calculation : Test Conditions
Given / Assumed
Symbol
Outside Diameter Tank 42 mtr D
Average thickness shell plate 7.8 mm
Shell height 2.47 mtr
Liquid Height 8.2 mtr Hc
Yield Strength 355 N/mm2 Ste 36 Re
Design pressure 0 mbar 1.1 x p = pt
0 if 10 mbar or less
Medium Water
Specific gravity medium 1 kg/l W
Calculation : Shell Course Thickness
et = (D/20.S).(98.W.(Hc-0.3)+p) + c
EEMUA159
0.80 x Re
Allowable Material Stress = 284 N/mm2 S
et = 5.72 mm
Result
Actual average plate thickness 7.8 mm
EEMUA159
0.80 x Re
Required plate thickness incl CA 5.72 mm
SUFFICIENT
GOVERNING
Comments
Ste 36 is equivalent to GH36 and has a Re value of 355 N/mm2
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3.10. 5th Shell course: Operating
EEMUA159 : 5th Shell Course Calculation : Design Conditions
Given / Assumed
Symbol
Outside Diameter Tank 42 mtr D
Average thickness shell plate 8.0 mm
Shell height 2.47 mtr
Liquid Height 5.73 mtr Hc
Yield Strength 235 N/mm2 Ste 37-2 Re
Corrossion Allowance 0 mm c
Design pressure 10 mbar p
Used in calculation 0 0 if 10 mbar or less
Medium Gasoil
Specific gravity medium 0.835 kg/l W
Calculation : Shell Course Thickness
ec = (D/20.S).(98.W.(Hc-0.3)+p) + c
EEMUA159
0.80 x Re
Allowable Material Stress = 188 N/mm2 S
ec = 4.96 mm
Result
Actual average plate thickness 8.0 mm
EEMUA159
0.80 x Re
Required plate thickness incl CA 4.96 mm
SUFFICIENT
NON GOVERNING
Comments
Ste 37-2 is equivalent to SJ235JR and has a Re value of 235 N/mm2
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3.11. 5th Shell course: Test
EEMUA159 : 5th Shell Course Calculation : Test Conditions
Given / Assumed
Symbol
Outside Diameter Tank 42 mtr D
Average thickness shell plate 8.0 mm
Shell height 2.47 mtr
Liquid Height 5.73 mtr Hc
Yield Strength 235 N/mm2 Ste 37-2 Re
Design pressure 0 mbar 1.1 x p = pt
0 if 10 mbar or less
Medium Water
Specific gravity medium 1 kg/l W
Calculation : Shell Course Thickness
et = (D/20.S).(98.W.(Hc-0.3)+p) + c
EEMUA159
0.80 x Re
Allowable Material Stress = 188 N/mm2 S
et = 5.94 mm
Result
Actual average plate thickness 8.0 mm
EEMUA159
0.80 x Re
Required plate thickness incl CA 5.94 mm
SUFFICIENT
GOVERNING
Comments
Ste 37-2 is equivalent to SJ235JR and has a Re value of 235 N/mm2
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3.12. 6th Shell course: Operating
EEMUA159 : 6th Shell Course Calculation : Design Conditions
Given / Assumed
Symbol
Outside Diameter Tank 42 mtr D
Average thickness shell plate 7.1 mm
Shell height 2.47 mtr
Liquid Height 3.26 mtr Hc
Yield Strength 235 N/mm2 Ste 37-2 Re
Corrossion Allowance 0 mm c
Design pressure 10 mbar p
Used in calculation 0 0 if 10 mbar or less
Medium Gasoil
Specific gravity medium 0.835 kg/l W
Calculation : Shell Course Thickness
ec = (D/20.S).(98.W.(Hc-0.3)+p) + c
EEMUA159
0.80 x Re
Allowable Material Stress = 188 N/mm2 S
ec = 2.71 mm
Result
Actual average plate thickness 7.1 mm
EEMUA159
0.80 x Re
Required plate thickness incl CA 2.71 mm
SUFFICIENT
NON GOVERNING
Comments
Ste 37-2 is equivalent to SJ235JR and has a Re value of 235 N/mm2
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3.13. 6th Shell course: Test
EEMUA159 : 6th Shell Course Calculation : Test Conditions
Given / Assumed
Symbol
Outside Diameter Tank 42 mtr D
Average thickness shell plate 7.1 mm
Shell height 2.47 mtr
Liquid Height 3.26 mtr Hc
Yield Strength 235 N/mm2 Ste 37-2 Re
Design pressure 0 mbar 1.1 x p = pt
0 if 10 mbar or less
Medium Water
Specific gravity medium 1 kg/l W
Calculation : Shell Course Thickness
et = (D/20.S).(98.W.(Hc-0.3)+p) + c
EEMUA159
0.80 x Re
Allowable Material Stress = 188 N/mm2 S
et = 3.24 mm
Result
Actual average plate thickness 7.1 mm
EEMUA159
0.80 x Re
Required plate thickness incl CA 3.24 mm
SUFFICIENT
GOVERNING
Comments
Ste 37-2 is equivalent to SJ235JR and has a Re value of 235 N/mm2
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3.14. 7th Shell course: Operating
EEMUA159 : 7th Shell Course Calculation : Design Conditions
Given / Assumed
Symbol
Outside Diameter Tank 42 mtr D
Average thickness shell plate 6.8 mm
Shell height 1.12 mtr
Liquid Height 0.79 mtr Hc
Yield Strength 235 N/mm2 Ste 37-2 Re
Corrossion Allowance 0 mm c
Design pressure 10 mbar p
Used in calculation 0 0 if 10 mbar or less
Medium Gasoil
Specific gravity medium 0.835 kg/l W
Calculation : Shell Course Thickness
ec = (D/20.S).(98.W.(Hc-0.3)+p) + c
EEMUA159
0.80 x Re
Allowable Material Stress = 188 N/mm2 S
ec = 0.45 mm
Result
Actual average plate thickness 6.8 mm
EEMUA159
0.80 x Re
Required plate thickness incl CA 0.45 mm
SUFFICIENT
NON GOVERNING
Comments
Ste 37-2 is equivalent to SJ235JR and has a Re value of 235 N/mm2
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3.15. 7th Shell course: Test
EEMUA159 : 7th Shell Course Calculation : Test Conditions
Given / Assumed
Symbol
Outside Diameter Tank 42 mtr D
Average thickness shell plate 6.8 mm
Shell height 1.12 mtr
Liquid Height 0.79 mtr Hc
Yield Strength 235 N/mm2 Ste 37-2 Re
Design pressure 0 mbar 1.1 x p = pt
0 if 10 mbar or less
Medium Water
Specific gravity medium 1 kg/l W
Calculation : Shell Course Thickness
et = (D/20.S).(98.W.(Hc-0.3)+p) + c
EEMUA159
0.80 x Re
Allowable Material Stress = 188 N/mm2 S
et = 0.54 mm
Result
Actual average plate thickness 6.8 mm
EEMUA159
0.80 x Re
Required plate thickness incl CA 0.54 mm
SUFFICIENT
GOVERNING
Comments
Ste 37-2 is equivalent to SJ235JR and has a Re value of 235 N/mm2
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3.16. Primary Wind Girder
Limited details were available on the design of this girder. Position and width of the girder were given factors.
EN14015 : Primary Wind Girder
Given / Assumed
Required Section Modulus Z
Total Height of tank 15.93 mtr Ht
Wind Speed 167.4 km/hr Vw
= 46.5 m/s
Diameter Tank 42 m D
Calculation
Section Modulus Required
Z = 0.058 . D2.Ht.(Vw2/452)
= 1740 cm3 Required
Current Top Stiffner
- Aka walkway Length 815 cm b
Width 8 cm assumed d
Section Modulus Available Z
Z = b.d2/6
= 8693 cm3 Available
Current Setup is: ACCEPTABLE
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3.17. Secondary stiffening ring
As standard Geldof use an angle profile of 150x150x10mm, which exceeds the minimum design requirements of the EN14015.
EN14015 : Secondary Stiffening Ring
Diameter of the tank 42 m D
Maximum space between secondary rings m HP
Stable full shell height m HE
Stable height per course m He
Height below girder m h
Minimum thickness top course 6.3 mm emin
Thickness of each course mm e
K-factor - K
Internal pressure 5 mbar pv
Wind speed 46.5 m/s Vw
Calculation He = h.(emin/e)5/2
e h He Sum h Sum He
Transformed height
difference
Effective height
difference
Effective height
[m]
Shell 1 12.8 2.46 0.42 2.46 0.42
Shell 2 10.2 2.47 0.74 4.93 1.16 Shell 3 10.1 2.47 0.76 7.4 1.92 Shell 4 7.8 2.47 1.45 9.87 3.37 1.36 2.32 9.72
Shell 5 8.0 2.47 1.36 12.34 4.73 Shell 6 8.1 2.47 1.83 14.81 6.56
HE 6.56 m HE = Sum He
K = 95000 / ((3.563*Vw2)+(580*pv))
= 8.96
HP = K.(emin5/D3)1/2
= 3.28 m Max distance between secondary rings
HP < HE < 2HP
3.28 < 6.56 < 6.56
Conclusion being, one (1) extra stiffening ring is required.
Spacing secondary girder = (Height of prim. girder- HZ)/3
2.75 mtr below primary girder
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3.18. Overturning moment
EN14015 : Overturning Moment
Given / Assumed
Overturning Moment kNm M
Lateral Force Coeeficient - assumed 1 G1
Lateral Force Coeeficient G2
Total Height Tank Shell 15.92 m HL
Effective mass of tank contents 7000 kg T1
Effective mass of tank contents - sloshing 8630 kg T2
Total weight of tank roof 16970 kg Tr
Total weight of tank shell 159209 kg Tt
Height bottom tank shell to centroid lat force T1 5.85 m X1
Height bottom tank shell to centroid lat force T2 9 m X2
Height bottom to COG Shell 6.76 m Xs
Site amplification factor, table G.1 1.5 j
Given / Assumed
T1 and T2 determined by means of figure G.1
X1 and X2 determined by means of figure G.2
Ks determined from figure G.3 = 0.63
Ts = 1.8. Ks.D1/2
= 7.35
G2 = 1.25.G1.j / Ts
= 0.26
M = (G1.((Tt.Xs)+(Tr.HL)+(T1.X1) + (G2.T2.X2)) / 102
= 13795.89 kN.m
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3.19. Restistance to overturning
EN14015 : Resistance to overturning
Given / Assumed
Maximum force of tank contents kNm WL
thickness anular plate 9.1 mm tab
Minimum Yield Strength anular ring 355 N/mm2 Reb
Maximum density cotained liquid 1 kg/l Ws
Maximum filling height 15.8 m HT
Calculation
WL = 0.1.tba.SQR(Reb.Ws.HT)
= 68.15 kN.m
Condition
WL <= Ws.HT.D
663.6 kN.m
OK
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3.20. Conclusion
Based on the assumptions regarding the materials, the following can be concluded:
- The wall thickness of all shell rings are sufficient considering the required wall thickness as stipulated EEMUA159 (80% of yield strength).
One extra secondary stiffening rings are required, allowing a maximum wind velocity of 46.5 m/s.
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4. Aluminium Dome Load
4.1. Dome details
Total Weight of the Dome : 16970 kg Nr. of support shoes : 35 Dead weight per shoe : 485 kg per shoe Used in FEM calculation : 500 kg (5000 N) Set-up: Fixed point : Annular ring Std Gavity : 9.8 m/s Loads : 500 per pipe shoe
4.2. Dome Load Analysis
See appendix A for the FEM calculation of the stresses in the shell as a result of the dome load..
4.2.1. Model setup
A FEM model has been set-up as follows:
- Small section of the tank modeled. 10.3° as there is 10.29° between IFR shoes. - Single IFR shoe modelled. - Wind girder modelled - 2x Stiffener modelled
- Annular plate as fixed point. - Loading from LC2 / 35, =1734.8 kN/35 = 49566 N per IFR shoe.
4.3. Result
The maximum simulated stress in the shell is 113 N/mm2, see appendix A for detailed results.
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5. Conclusion
Jacking of the vessel using 36 brackets results in a maximum stress of 54 N/mm2, well within the allowable limits.
A stability analysis shows that a single extra secondary wind girder is required, allowing a maximum wind velocity of 46.5 m/s
The vessel is capable of supporting the new aluminum dome as designed. The FEM analysis of the dome weight on the shell result in a maximum stress of 113 N/mm2.
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A. FEM calculations dome load in shell
A.1.1 Model properties
Study name Dome load
Analysis type Stress
Mesh type Mixed Mesh
Number of modes 1
Solver type FFEPlus
Incompatible bonding options Automatic
Thermal Effect: On
Thermal option Include temperature loads
Zero strain temperature 298 Kelvin
Include fluid pressure effects from SOLIDWORKS Flow Simulation
Off
Soft Spring: Off
Result folder SOLIDWORKS document (D:\IPSS\Geldof 2016-009\Vijzelen\Buckling)
A.1.2 Units
Unit system: SI (MKS)
Length/Displacement mm
Temperature Kelvin
Angular velocity Rad/sec
Pressure/Stress N/m^2
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A.1.3 Material Properties
Model Reference Properties Components
Name: 1.0044 (S275JR)
Model type: Linear Elastic Isotropic
Default failure criterion: Unknown
Yield strength: 2.75e+008 N/m^2
Tensile strength: 4.1e+008 N/m^2
Elastic modulus: 2.1e+011 N/m^2
Poisson's ratio: 0.28
Mass density: 7800 kg/m^3
Shear modulus: 7.9e+010 N/m^2
Thermal expansion coefficient:
1.1e-005 /Kelvin
SolidBody 1(Cut-Extrude1)(Anular ring b-1),
SolidBody 1(Cut-Extrude2)(ring 1b-1)
Curve Data:N/A
Name: Plain Carbon Steel
Model type: Linear Elastic Isotropic
Default failure criterion: Unknown
Yield strength: 2.20594e+008 N/m^2
Tensile strength: 3.99826e+008 N/m^2
Elastic modulus: 2.1e+011 N/m^2
Poisson's ratio: 0.28
Mass density: 7800 kg/m^3
Shear modulus: 7.9e+010 N/m^2
Thermal expansion coefficient:
1.3e-005 /Kelvin
SolidBody 1(Boss-Extrude1)(IFR shoe-1/guide-1),
SolidBody 1(Boss-Extrude1)(IFR shoe-1/plaat-1),
SolidBody 1(Cut-Extrude1)(angle-1),
SolidBody 1(Cut-Extrude1)(stiffener b-1),
SolidBody 1(Cut-Extrude1)(stiffener b-2),
SolidBody 1(Cut-Extrude1)(windligger b-1)
Curve Data:N/A
Name: 1.0037 (S235JR)
Model type: Linear Elastic Isotropic
Default failure criterion: Unknown
Yield strength: 2.35e+008 N/m^2
Tensile strength: 3.6e+008 N/m^2
SolidBody 1(Fillet1)(IFR shoe-1/support 1-1),
SolidBody 1(Cut-Extrude1)(ring 2b-1),
SolidBody 1(Cut-Extrude1)(ring 3b-1),
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Elastic modulus: 2.1e+011 N/m^2
Poisson's ratio: 0.28
Mass density: 7800 kg/m^3
Shear modulus: 7.9e+010 N/m^2
Thermal expansion coefficient:
1.1e-005 /Kelvin
SolidBody 1(Cut-Extrude1)(ring 4b-1),
SolidBody 1(Cut-Extrude1)(ring 5b-1),
SolidBody 1(Cut-Extrude1)(ring 6b-1),
SolidBody 1(Cut-Extrude1)(ring 7b-1),
SolidBody 1(Cut-Extrude1)(top ring support b-1)
Curve Data:N/A
A.1.4 Loads and Fixtures
Fixture name Fixture Image Fixture Details
Fixed-1
Entities: 1 face(s)
Type: Fixed Geometry
Resultant Forces
Components X Y Z Resultant
Reaction force(N) 1.45425 96503.4 1.71269 96503.4
Reaction Moment(N.m) 0 0 0 0
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Load name Load Image Load Details
Gravity-1
Reference: Top Plane
Values: 0 0 -9.81
Units: m/s^2
Force-1
Entities: 1 face(s)
Type: Apply normal force
Value: 49566 N
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A.2 Mesh
Mesh type Solid Mesh
Mesher Used: Curvature-based mesh
Jacobian points 4 Points
Maximum element size 473.231 mm
Minimum element size 94.6462 mm
Mesh Quality Plot High
Remesh failed parts with incompatible mesh On
A.2.1 Mesh details
Total Nodes 25780
Total Elements 12361
Maximum Aspect Ratio 15531
% of elements with Aspect Ratio < 3 5.51
% of elements with Aspect Ratio > 10 37.4
% of distorted elements(Jacobian) 0
Time to complete mesh(hh;mm;ss): 00:00:02
Computer name: MSBE
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A.2.3 Mesh control
Mesh Control Name Mesh Control Image Mesh Control Details
Control-1
Entities: 1 component(s)
Units: mm
Size: 88.7519
Ratio: 1.5
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A.3 Results
A.3.1 Stresses
Name Type Min Max
Stress1 VON: von Mises Stress
1.288e-005N/mm^2 (MPa)
Node: 11290
1.133e+002N/mm^2 (MPa)
Node: 562
Buckling-Static 1-Stress-Stress1
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A.3.1 Displacement
Name Type Min Max
Displacement1 URES: Resultant Displacement 0.000e+000mm
Node: 5
7.809e+001mm
Node: 10237
Buckling-Static 1-Displacement-Displacement1
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A.3.1 Equivalent strain
Name Type Min Max
Strain1 ESTRN: Equivalent Strain 8.908e-011
Element: 4107
1.787e-004
Element: 7323
Buckling-Static 1-Strain-Strain1