The reeling technique presents an economical pipeline installation method for offshore oil and gas applications, especially for thick-wall (low D/t) pipelines. During reeling, the pipe is subjected to large plastic bending strains up to 3%. In thick-wall pipes, the tensile fracture response of the pipeline/girth weld would normally be the governing limit state. Seamless line pipes are preferred for the reeling applications in which the Lüders plateau is often exhibited in materials stress-strain response. In this paper, the fracture response of such pipelines is investigated from a continuum perspective using a nonlinear 3D finite element analysis. A typical pipeline with a hypothetical defect is considered, with the material having a range of Lüders strains and strain hardening indices. Results show that the Lüders plateau modifies the shape of the moment-strain response curves of the pipe, as well as the J-integral fracture response. It is observed that the response is always bounded between two limiting material models, which are (i) the elastic-perfectly plastic stress-strain response and (ii) the conventional elastic-strain hardening plasticity response, without a Lüders plateau. Also, the Lüders plateau was observed to decrease the crack opening stress ahead of the crack tip and thus the crack tip constraint. On the other hand, the presence of a Lüders plateau elevates the near tip plastic strain and stress triaxiality fields, thus promoting ductile fracture. A micromechanical damage integral model coupled with a modified boundary layer analysis was incorporated to study this aspect. Based on the findings of this study, it is believed that the presence of Lüders plateau could significantly alter the fracture response and toughness of pipes subject to relatively high strains.

1.
2000, Offshore Standard DNV-OS-F101—Submarine Pipeline Systems, Det Norske Veritas, Hovik, Norway.
2.
2006, Offshore Standard DNV-RP-F108—Fracture Control for Pipeline Installation Methods Introducing Cyclic Plastic Strain, Det Norske Veritas, Hovik, Norway.
3.
Hutchinson
,
J. W.
, 1983, “
Fundamentals of the Phenomenological Theory of Nonlinear Fracture Mechanics
,”
ASME J. Appl. Mech.
0021-8936,
50
, pp.
1042
1051
.
4.
Kumar
,
V.
,
German
,
M. D.
, and
Shih
,
C. F.
, 1981, “
An Engineering Approach for Elastic-Plastic Fracture Analysis
,” Electric Power Research Institute, EPRI Report No. NP-1931.
5.
Ainsworth
,
R. A.
, 1984, “
The Assessment of Defects in Structures of Strain Hardening Material
,”
Eng. Fract. Mech.
0013-7944,
19
(
4
), pp.
633
642
.
6.
Nourpanah
,
N.
, and
Taheri
,
F.
, 2010, “
Development of a Reference Strain Approach for Assessment of Fracture Response of Reeled Pipelines
,”
Eng. Fract. Mech.
0013-7944,
77
,
2337
2553
.
7.
Kyriakides
,
S.
,
Ok
,
A.
, and
Corona
,
E.
, 2008, “
Localization and Propagation of Curvature Under Pure Bending in Steel Tubes With Lüders Bands
,”
Int. J. Solids Struct.
0020-7683,
45
, pp.
3074
3087
.
8.
Kyriakides
,
S.
, and
Corona
,
E.
, 2007,
Mechanics of Offshore Pipelines: Volume 1 Buckling and Collapse
,
1st ed.
,
Elsevier
,
New York
.
9.
2008, ABAQUS Version 6.8 Theory Manual, Simulia, RI.
10.
Østby
,
E.
,
Jayadevan
,
K. R.
, and
Thaulow
,
C.
, 2005, “
Fracture Response of Pipelines Subject to Large Plastic Deformation Under Bending
,”
Int. J. Pressure Vessels Piping
0308-0161,
82
, pp.
201
215
.
11.
Pisarski
,
H. G.
, and
Cheaitani
,
M. J.
, 2008, “
Development of Girth Weld Flaw Assessment Procedures for Pipelines Subjected to Plastic Straining
,”
Int. J. Offshore Polar Eng.
1053-5381,
18
(
3
), pp.
183
187
.
12.
Parks
,
D. M.
, 1992, “
Advances in Characterization of Elastic-Plastic Crack-Tip Fields
,”
Topics in Fracture and Fatigue
,
A. S.
Argon
, ed.,
Springer
,
New York
, pp.
59
98
.
13.
O’Dowd
,
N. P.
, and
Shih
,
C. F.
, 1992, “
Family of Crack-Tip Fields Characterized by a Triaxiality Parameter––II. Fracture Applications
,”
J. Mech. Phys. Solids
0022-5096,
40
(
5
), pp.
939
963
.
14.
Hutchinson
,
J. W.
, 1968, “
Singular Behavior at the End of a Tensile Crack in a Hardening Material
,”
J. Mech. Phys. Solids
0022-5096,
16
, pp.
13
31
.
15.
Rice
,
J. R.
, and
Rosengren
,
G. R.
, 1968, “
Plane Strain Deformation Near a Crack Tip in a Power-Law Hardening Material
,”
J. Mech. Phys. Solids
0022-5096,
16
, pp.
1
12
.
16.
Shih
,
C. F.
, 1983, “
Tables of Hutchinson-Rice-Rosengren Singular Field Quantities
,” Brown University, Report No. MRL E-147.
17.
O’dowd
,
N. P.
, 1995, “
Applications of Two Parameter Approaches in Elastic-Plastic Fracture Mechanics
,”
Eng. Fract. Mech.
0013-7944,
52
(
3
), pp.
445
465
.
18.
Faleskog
,
J.
, 1995, “
Effects of Local Constraint Along Three-Dimensional Crack Fronts—A Numerical and Experimental Investigation
,”
J. Mech. Phys. Solids
0022-5096,
43
, pp.
447
465
.
19.
Pisarski
,
H. G.
,
Phaal
,
R.
,
Hadley
,
I.
, and
Francis
,
R.
, 1994, “
Integrity of Steel Pipe During Reeling
,”
International Conference on Offshore Mechanics and Arctic Engineering (OMAE)
, Houston, TX, Vol.
5
, pp.
189
198
.
20.
Anderson
,
T. L.
, 2005,
Fracture Mechanics Fundamentals and Applications
,
3rd ed.
,
CRC
,
Boca Raton, FL
.
21.
Brocks
,
W.
, and
Schmitt
,
W.
, 1995, “
The Second Parameter in J-R Curves: Constraint or Triaxiality?
,”
ASTM STP 1244: Constraint Effects in Fracture Theory and Applications: Second Volume
,
M.
Kirk
and
A.
Bakker
, eds.,
American Society for Testing and Materials
,
Philadelphia, PA
.
22.
Anderson
,
T. L.
,
Vanaparthy
,
N. M. R.
, and
Dodds
,
R. H.
, Jr.
, 1993, “
Predictions of Specimen Size Dependence on Fracture Toughness for Cleavage and Ductile Tearing
,”
ASTM STP 1171: Constraint Effects in Fracture
,
American Society For Testing and Materials
,
Philadelphia, PA
, pp.
123
134
.
23.
Rice
,
J. R.
, and
Tracey
,
D. M.
, 1969, “
On the Ductile Enlargement of Voids in Triaxial Stress Fields
,”
J. Mech. Phys. Solids
0022-5096,
17
, pp.
201
217
.
24.
Williams
,
M. L.
, 1957, “
On the Stress Distribution at the Base of a Stationary Crack
,”
ASME J. Appl. Mech.
0021-8936,
24
, pp.
111
114
.
25.
Nourpanah
,
N.
, and
Taheri
,
F.
, “
A Numerical Study on the Crack Tip Constraint of Pipelines Subject to Extreme Plastic Bending
,”
Eng. Fract. Mech.
0013-7944, in press.
26.
O’Dowd
,
N. P.
, and
Shih
,
C. F.
, 1991, “
Family of Crack-Tip Fields Characterized by a Triaxiality Parameter––I. Structure of Fields
,”
J. Mech. Phys. Solids
0022-5096,
39
(
8
), pp.
989
1015
.
You do not currently have access to this content.