574()-363-370.hwpAPI-X80
Large Deformation Inelastic Analysis of API-X80 Steel Linepipes
* ** *** **** †
Lee, Seung-Jung Yoon, Young-Cheol Cho, Woo-Yeon Yu, Seong-Mun Zi, Goangseup
( : 2009 6 12 ; : 2009 6 30)
················································································································································································································

API-X80 .
GTN(Gurson-Tvergaard-Needleman) .
ABAQUS (User Subroutine)
(UMAT) . GTN
. API-X80
.
: API-X80, , , , GTN ,
Abstract
We simulated large deformation and inelastic behavior of API-X80 steel linepipes using nonlinear finite element method.
Gurson-Tvergaard-Needleman(GTN) model is employed for the development of the constitutive model of the steel. The GTN model
is implemented in the form of the user-supplied material subroutine(UMAT) for the commercial software of ABAQUS. To calibrate
the model parameters, we simulated the behavior of the uniaxial tension test using ABAQUS equipped with the developed GTN
model. Using the set of the model parameters, we were able to capture the characteristics of the plastic buckling of API-X80 steel
linepipes.
model parameters
Tel: 02-3290-3324 ; Fax: 02-928-7656
**
***
2009 10 31
2009 12 .
1.
,

, .

, API-X65, X70
API-X80
. API-X80


. ,
API-X80
.


0.2% .
API-X80
364 22 4(2009.8)
1

.
Mcclitock(1968)
, Rice
Tracey(1969)
(spherical void)
. Gurson(1977)

. Tvergaard
Needleman(1984) Gurson GTN
(Gurson-Tvergaard-Needleman) .
,
GTN
(
, 2008; Acharyya , 2008; Oh , 2007).


.

.
(Belytschko , 1999; Moes , 1999; Zi
, 2003; 2004; 2005) (Bordas ,
2008; Rabczuk , 2007; Zi , 2007) .
.

. ABAQUS
GTN API-X80
. GTN
User Subroutine
(UMAT) ABAQUS
. GTN


.
2.1 GTN
(Nucleation), (Growth), (Coalescence)

,

,

.
(1984) Gurson
(effective void
volume fraction)
. Gurson GTN
,

.
(1) .


. GTN
.





≤


≥
.
,

22 4(2009.8) 365
2
,

.

,
. (3) .

.
(4)
(5)
(6)

(7) .










, ,
.


exponent), ,
.
(8)
.
2.2
GTN

. 2.1

.
.
ABAQUS/Standard User Subroutine
. User Subroutine
UMAT(User-defined material)
. UMAT
ABAQUS

. ABAQUS

.
GTN UMAT
. UMAT
Aravas(1987) .
GTN
9 ABAQUS input
.
GTN

. 2007 API
specification API-X80
2 . 3
1 .


API-X80
366 22 4(2009.8)
3
(a)
(b)
A D G R a b
45 8.9 35.6 6 10 35
1 (mm)
y=0 z=0 x=0
y=0 z=0 x=0 y=10
2

.
. 4(a)
1/8 , 4(b) 2
1, 2, 3 4
.
.

.
10mm
8 3 C3D8(8-node linear
brick) .
.

.

.
,
0.7mm×0.7mm .
3.2 GTN
3.2.1
2 11 . 11

, Franklin(1969) (9)
.
()
. API-X80 30ppm,
1.8% ( , 2007)
, 0 .

. , 9 API-
X80
. ,

.
.
(8)
.














22 4(2009.8) 367
5
(a)
(b)
6


(MPa)
4
,
,
5 . ,
200MPa 0.3 .
3.2.2
6 . 6(a)

, 6(b)
. experiment
1~4 , FE result 1~4
. 6
GTN
. 6(a)

GTN
.
3
. API-X80
,
.
, ,
.
4
. 1 2
, , .
4.
4.1
GTN
API-X80
368 22 4(2009.8)
7 8
(a) 1 (b) 2 (c) 3
10 Von Mises
(a) 1 (b) 2 (c) 3
9

2007
.


.

(imperfection)
.
7 4.750mm 10MN
UTM(Universal Testing Machine) 300
.

, LVDT(Linear
Variable Differential Transformation)
.
(2007) .
8
1/2 .
8 3 C3D8I(8-node linear
brick, incompatible modes) .
7
8
.
surface 1
x y
.
100kN
z 500mm
.
. 9

. .
4.2.2


.


0.5, 1.0, 5.0[mm]
.

22 4(2009.8) 369
11 -
0.0205 0.0181 0.0131
.
.

11 . GTN
1
.
,
400mm
(11) .
(11)
.

.
GTN
.

. (12)~(13) .



. (13) .
11
.
0.5 1.0
5.0 ,
.
, 11
6
.
ABAQUS
API-X80
. .
(1) GTN

.
API-X80

. ,
API-X80


.

.
.
(3) GTN

.


.

.
GTN
.
(4) GTN


.
370 22 4(2009.8)

Design 2009
(ADD-06-05-06)
,
.

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