internal pressure able to compensate the total
concreting loads.
It provides
weather protection during the con-
struction phase of the inner steel tank and the
installation of the bottom insulation (Icing, snow
and wind condition).
The steel plates are closely connected to the con-
crete by studs.
Annexes A & B have been added to show the
steel roof erection phases.
The study has been performed in finite elements.
The software used is ESA-Prima Win Version 3.50
from the company SCIA
Calculation rules:
The elements dimensioning is in suit with the fol-
lowing European regulation:
• EC3 for the verifications
• EC1 for the climatic loads
• Standards and DTU in force relating to steel
structures
LNG tanks (two)
General data
Height
: 49 metres
Diameter
: 76 metres
Capacity
: 125 000 cubic metres each
Storage temperature
: -163°C
Completion
: LNG1, July 2005, LNG 2, August
2005
Main contractor, storage tanks and ship load-
ing systems
: Tractebel Industry Engineering
Sub-contractors
:
Outfitting: Entrepose Contract-
ing
Installation of ship loading system and low-pres-
sure flare: Fabricom Concrete work:
NCC
Model & boundary conditions
Type of structure
• Number of nodes: 2352
• Number of members: 1543
• Number of 1D macros: 177
• Number of bound. lines: 2356
• Number of 2D macros:1121
• Number of profiles: 8
• Number of cases:13
• Number of materials: 2
Material
S 275
S 355
List of material
The total
weight of the structure
: 620891,84 kg
Group of members
: 1/1543
Macro2D Group of members
: 1/1124
Conclusion
• The linear analysis confirms that all individual
load and loads combination are acceptable
regarding the EC.3 (with applicable safety fac-
tors and allowable stresses).
• The governing case is the 3rd case for non
uniform snow load; the actual steel allows a
concrete pouring in one layer with pressuriza-
tion of the steel roof.
• A survey of the snow height on the roof is
required to guaranty the snow limit of the uni-
form case.
• The next governing case is the 7th case for
internal pressurization before concreting of
the steel roof.
• The structural beam and liner plates are suit-
able for the climatic condition and for the con-
struction loads at different stages during win-
ter time and before concrete pouring of the
dome roof.
• Non linear analysis of 2nd order according
EC3
made the demonstration of the
model
convergence, there no plastic zone in the
model after 50 iterations of 2nd order.
Steel roof erection phases
The purpose of the second part is to demonstrate
that the erection phase of the steel roof will not
produce over-stresses, excessive deformation
and displacements in the roof element or in the
central
mast by a FEA verification at different
stages of the erection procedure E066-AS-M-KK-
0104 (86600-EE35-PPR-104) to insure the final
shape of the structure.
The calculation note is aiming at verifying the
steel elements part of the LNG container roof.
The study has been performed in finite elements.
The software used is ESA-Prima Win Version 3.50
from the company SCIA.
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