Code_Aster ®
Version
5.0
Titrate:
SDLS108 Utilization of RIGI_PARASOL within the framework of a study EPR
Date:
30/08/01
Author (S):
G. DEVESA, Key P. LATRUBESSE
:
V2.03.108-A Page:
1/6

Organization (S): EDF/RNE/AMV, SAMTECH-France
Handbook of Validation
V2.03 booklet: Linear dynamics of the hulls and plates
V2.03.108 document

SDLS108 - Utilization of option RIGI_PARASOL
within the framework of a study EPR

Summary:

The goal of the test is to test the option RIGI_PARASOL which makes it possible to distribute stiffnesses of floor under a foundation raft of
building. This option is called successively in commands AFFE_CARA_ELEM and
CALC_AMOR_MODAL.

In command AFFE_CARA_ELEM, it makes it possible to calculate then to affect by a modeling DIS_TR them
specific stiffnesses of a carpet of springs of floor under the foundation raft of building. In the command
CALC_AMOR_MODAL, these values make it possible to calculate modal potential energy in the ground which contributes
with the calculation of modal depreciation according to the rule of the RCC-G [bib1].

The studied case is an industrial structure of the nuclear small island of EPR. It includes/understands only one modeling. It
case test is thus used to test nonthe regression of the code as much as it constitutes documentation on its use
in oneself. The model of approximately 40000 degrees of freedom consists of 6700 nodes and 10300 elements approximately:
9500 elements DKT, 100 elements of beam and 700 discrete elements of connection.

This industrial case-test is representative of the studies led by SEPTEN/ms on modelings 3D of
civil engineering subjected to the seism and makes it possible to reabsorb the tools used within this framework. The comparison relates to
frequencies and depreciation for the first modes calculated on carpet of springs of ground.
The values of reference for a ground of the type SA (soft ground) are given in note E.N.T.MS 96.052 A
[bib2].
The 6 values of total stiffnesses of ground to be distributed under the foundation raft are determined by PARASOL for
modulate ground of the type SA (444 MPa).
Handbook of Validation
V2.03 booklet: Linear dynamics of the hulls and plates
HT-62/01/012/A

Code_Aster ®
Version
5.0
Titrate:
SDLS108 Utilization of RIGI_PARASOL within the framework of a study EPR
Date:
30/08/01
Author (S):
G. DEVESA, Key P. LATRUBESSE
:
V2.03.108-A Page:
2/6

1
Problem of reference

1.1 Geometry


The studied case is the industrial structure of the nuclear small island of EPR. It includes/understands only one modeling
composed primarily of elements of hull. The connection of the foundation with the ground is modelled
by specific discrete elements.

A number of nodes: 6732
A number of triangular meshs (TRIA3): 1848
A number of rectangular meshs (QUAD4): 7677
A number of POI1: 1119
A number of SEG2: 9047
Handbook of Validation
V2.03 booklet: Linear dynamics of the hulls and plates
HT-62/01/012/A

Code_Aster ®
Version
5.0
Titrate:
SDLS108 Utilization of RIGI_PARASOL within the framework of a study EPR
Date:
30/08/01
Author (S):
G. DEVESA, Key P. LATRUBESSE
:
V2.03.108-A Page:
3/6

1.2
Material properties

Reinforced concrete:

E =
35000.
MPa
Naked =
0.2
AMOR_ALPHA = 4.95E-04
AMOR_BETA =
3.91

Various distributions of the densities of reinforced concrete following the components:

To erase
RHO = 2500 kg/m3
External walls
RHO = 2500 kg/m3
Floors of the boxes RHO = 2500 kg/m3
Internal structures
RHO = 2500, 12500, 9700, 5850, 5290, 4500, 4180, 3900, 3680, 620 kg/m3
External enclosure
RHO = 2500 kg/m3
Division 0
RHO = 2500, 5000, 4500, 4180, 3750 kg/m3
Division 1
RHO = 2500, 4500, 3410 kg/m3
Division 2-3
RHO = 2500, 4500, 4180, 3900 kg/m3
Division 4
RHO = 42500, 500, 3410 kg/m3

Concrete prestressed:

E =
40000
MPa
Naked =
0.2
RHO =
2500
kg/m3
AMOR_ALPHA = 3.54
E-04
AMOR_BETA =
2.79

Used for the internal enclosure.

1.3 Characteristics
elementary

To erase
thicknesses of hull 8, 4.5, 4 m
External enclosure
thickness 1.3 m
Internal enclosure
thicknesses 2.5, 1.3, 0.9 m
External walls
thicknesses 1.3, 0.9 m
Floors of the boxes thickness 0.6 m
Internal structures
thicknesses 7.5, 2.8, 1.9, 1.5, 1.2, 1.0, 0.8, 0.6, 0.5 m
Division 0
thicknesses 3, 2.5, 2.0, 1.5, 1, 0.8, 0.6, 0.5, 0.4, 0.3 m
Division 2-3
thicknesses 0.8, 0.7, 0.6, 0.5, 0.4, 0.3 m
Beams squares dig height = 0.5 m, thickness = 0.25 m
Division 1
thicknesses 1.1, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3 m
Beams squares dig height = 0.5 m, thickness = 0.25 m
Division 4
thicknesses 1.1, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3 m
Beams squares dig height = 0.5 m, thickness = 0.25 m

Stiffnesses of ground resulting from PARASOL:

Stiffnesses of the foundation raft:

Kx = 3.3 E10 NR/m
Ky = 3.3 E10 NR/m
Kz = 3.3 E10 NR/m
Krx = 6.01 E13 N.m
Kry = 5.76 E13 N.m
Krz = 5.76 E13 N.m

Co-ordinates of the center: 0. 0. ­ 11.6 m
Handbook of Validation
V2.03 booklet: Linear dynamics of the hulls and plates
HT-62/01/012/A

Code_Aster ®
Version
5.0
Titrate:
SDLS108 Utilization of RIGI_PARASOL within the framework of a study EPR
Date:
30/08/01
Author (S):
G. DEVESA, Key P. LATRUBESSE
:
V2.03.108-A Page:
4/6

2
Reference solution

2.1
Method of calculation used for the reference solution

The modal damping coefficients are calculated according to the rule of the RCC-G [bib1]. They are
obtained by summoning depreciation of the substructures constitutive of a building and them
depreciation structural and geometrical of the ground balanced by their respective rates of energy
potential compared to total potential energy, and that for each mode. There are 2 methods and
two key words of CALC_AMOR_MODAL to estimate the contribution of the ground with the potential energy according to
that one average modal efforts (key word “RIGI_PARASOL”) or modal displacements
(key word “DEPL”) with the nodes of the foundation raft.

2.2
Results of reference

The results of reference, frequencies, masses effective and modal depreciation are provided
in the note bench-mark datum [bib2]. They were calculated by Code_Aster.
It should be noted that modal depreciation was also calculated by affecting a stiffness to
each node of the foundation raft (instead of RIGI_PARASOL).

2.3
Uncertainty on the solution

Results of the industrial study. The case-test is thus included/understood like a test of not-regression of
code.

2.4 References
bibliographical

[1]
RCC-G Rčgles of design and construction of nuclear small islands REP - EDF - Direction
of Equipement - Edition July 1988
[2]
EPR Basic Design dynamic analyzes - modal Modelling and analysis off NR. I. buildings - note
E.N.T.MS 96.052 A

3 Modeling
With

3.1
Characteristics of modeling

PHENOMENON formulation: “MECHANICAL”, MODELING: DKT.

3.2
Characteristics of the grid

A number of nodes: 6732
A number of meshs and type: 7677 QUAD4 and 1848 TRIA3

3.3 Functionalities
tested

Commands


AFFE_CARA_ELEM RIGI_PARASOL
CARA


VALE

MODE_ITER_INV
CALC_FREQ FREQ


OPTION
“PROCHE”
POST_ELEM ENER_POT


CALC_AMOR_MODAL ENERSOL
METHODE
“RIGI_PARASOL”
AMOR_INTERN

“DEPL”
AMOR_SOL


Handbook of Validation
V2.03 booklet: Linear dynamics of the hulls and plates
HT-62/01/012/A

Code_Aster ®
Version
5.0
Titrate:
SDLS108 Utilization of RIGI_PARASOL within the framework of a study EPR
Date:
30/08/01
Author (S):
G. DEVESA, Key P. LATRUBESSE
:
V2.03.108-A Page:
5/6

4
Results of modeling A

4.1 Depreciation
Frequencies modes
Depreciation (%)
Results of
Variations reference -
(Hz)
with RIGI_PARASOL
reference (%)
calculation with
threshold = 30%
Code_Aster (%)
1 1.17453
20.905
20.905
0
2
1.17782
21.052
21.052
0
3 1.35640
30.000

30.000
0
4 2.16990
30.000

30.000
0
5
2.27813
29.925
29.925
0

Modes Frequencies Depreciation (%)
Results of
Variations reference -
(Hz)
with RIGI_PARASOL
reference (%)
calculation with
without threshold
Code_Aster (%)
1 1.17453
20.905
20.905 0
2
1.17782
21.052
21.052
0
3 1.35640
54.970
54.970
0
4 2.16990
30.223
30.223
0
5
2.27813
29.925
29.925
0

Modes Frequencies Depreciation (%)
Results of
Variations reference -
(Hz)
with DEPL
reference (%)
calculation with
threshold = 30%
Code_Aster (%)
1 1.17453
21.033
21.033
0
2 1.17782
21.183
21.183
0

3 1.35640
30.000
30.000
0
4 2.16990
30.000
30.000
0
5 2.27813
30.000
30.000
0


4.2 Parameters
of execution

Version: 5.02



Machine: SGI ORIGIN 2000



Obstruction memory:
400 megawords
Time CPU to use:
258 seconds
Handbook of Validation
V2.03 booklet: Linear dynamics of the hulls and plates
HT-62/01/012/A

Code_Aster ®
Version
5.0
Titrate:
SDLS108 Utilization of RIGI_PARASOL within the framework of a study EPR
Date:
30/08/01
Author (S):
G. DEVESA, Key P. LATRUBESSE
:
V2.03.108-A Page:
6/6

5
Summary of the results

Results of the depreciation obtained by CALC_AMOR_MODAL with the method of the forces
(key word “RIGI_PARASOL”) with or without truncation of threshold to 30% are exactly the same ones as
those given in the reference [bib2]. They are very close to those obtained by CALC_AMOR_MODAL
with the method of displacements (key word “DEPL”), also identical to those given in
reference [bib2].

Handbook of Validation
V2.03 booklet: Linear dynamics of the hulls and plates
HT-62/01/012/A

Outline document