Abstract

The durability and damage tolerance of laminated composites are critical design considerations for airframe composite structures. Therefore, the ability to model damage initiation and growth and predict the life of laminated composites is necessary to achieve efficient and economical structural designs. The purpose of the research presented in this paper is to experimentally verify the application of the damage model developed by the authors to predict progressive damage development in a toughened material system. Damage growth, stiffness degradation, and residual strength were experimentally determined for cross-ply and quasi-isotropic IM7/5260 graphite/bismaleimide laminates due to monotonic and tension-tension fatigue. The damage model, which has been implemented into a finite element code, was used to predict the stiffness loss and residual strength of unnotched and notched laminates. The model predictions were in good agreement to experimental results for several different fatigue loading histories and several different laminate stacking sequences.

References

1.
Reifsnider
,
K. L.
, “
Fatigue Behavior of Composite Materials
,”
International Journal of Fracture
, Vol.
16
, No.
6
,
12
1980
, pp.
563
-
583
.
2.
Reifsnider
,
K. L.
, “
The Mechanics of Fatigue in Composite Laminates
,”
Composite Materials
,
K.
Kawata
and
T.
Adasada
, Eds.,
Proceedings
,
Japan-U.S. Conference
,
Tokyo
,
1981
, pp.
131
-
144
.
3.
Talug
,
A.
and
Reifsnider
,
K. L.
, “
Analysis of Stress Fields in Composite Laminates with Interior Cracks
,”
Fiber Science and Technology
, Vol.
12
,
1979
, pp.
201
-
215
.
4.
O’Brien
,
T. K.
, “
Towards a Damage Tolerance Philosophy for Composite Materials and Structures
,”
Composite Materials: Testing and Design (Ninth Volume)
, ASTM STP 1059,
S. P.
Garbo
, Ed.,
American Society for Testing and Materials
,
West Conshohocken, PA
,
1990
, pp.
7
-
33
.
5.
Chang
,
Fu-Kuo
and
Chang
,
Kuo-Yen
, “
A Progressive Damage Model for Laminated Composites Containing Stress Concentrations
,”
Journal of Composite Materials
, Vol.
21
,
09
1987
, pp.
834
-
855
.
6.
Chamis
,
C. C.
,
Murphy
,
P. L. N.
, and
Minnetyan
,
L.
, “
Structural Behavior of Composites with Progressive Fracture
,”
Journal of Reinforced Plastics and Composites
, Vol.
11
,
04
1992
, pp.
413
-
442
.
7.
Talreja
,
R.
, “
A Continuum Mechanics Characterization of Damage in Composite Materials
,”
Proceedings, R. Soc. London
, Vol.
399A
,
1985
, pp.
126
-
216
.
8.
Talreja
,
R.
, “
Residual Stiffness Properties of Cracked Composite Laminates
,”
Advances in Fracture Research, Proceedings of the Sixth International Conference De Fracture
,
New Delhi, India
, Vol.
4
,
1985
, pp.
3013
-
3019
.
9.
Talreja
,
R.
, “
Transverse Cracking and Stiffness Reduction in Composite Laminates
,”
Journal of Composite Materials
, Vol.
19
,
1985
, pp.
355
-
375
.
10.
Vakulenko
,
A. A.
and
Kachanov
,
M. L.
, “
Continuum Theory of Cracked Media
,”
Izv. AN SSR. Mekhaniha Tverdogo Tela
, Vol.
6
,
1971
, p. 159.
11.
Harris
,
C. E.
,
Allen
,
D. H.
, and
O’Brien
,
T. K.
, “
Progressive Failure Methodologies for Predicting Residual Strength and Life of Laminated Composites
,”
Proceedings of the First NASA Advanced Composites Technology Conference
, 30 Oct.–1 Nov. 1990.
12.
Allen
,
D. H.
,
Groves
,
S. E.
, and
Harris
,
C. E.
, “
A Cumulative Damage Model for Continuous Fiber Composite Laminates with Matrix Cracking and Interply Delamination
,”
Composite Materials: Testing and Design (Eighth Conference)
, ASTM STP 972,
J. D.
Whitcomb
, Ed.,
American Society for Testing and Materials
,
West Conshohocken, PA
,
1988
, pp.
57
-
80
.
13.
Allen
,
D. H.
,
Harris
,
C. E.
, and
Groves
,
S. E.
, “
A Thermomechanical Constitutive Theory for Elastic Composites with Distributed Damage-I. Theoretical Development
,”
International Journal of Solids and Structures
, Vol.
23
, No.
9
,
1987
, pp.
1301
-
1318
.
14.
Allen
,
D. H.
,
Harris
,
C. E.
, and
Groves
,
S. E.
, “
A Thermomechanical Constitutive Theory for Elastic Composites with Distributed Damage-II. Application to Matrix Cracking in Laminated Composites
,”
International Journal of Solids and Structures
, Vol.
23
, No.
9
,
1987
, pp.
1319
-
1338
.
15.
Lee
,
J. W.
,
Allen
,
D. H.
, and
Harris
,
C. E.
, “
Internal State Variable Approach for Predicting Stiffness Reductions in Fibrous Laminated Composites with Matrix Cracks
,”
Journal of Composite Materials
, Vol.
23
,
12
1989
, pp.
1273
-
1291
.
16.
Lo
,
D. C.
,
Allen
,
D. H.
, and
Harris
,
C. E.
, “
A Continuum Model for Damage Evolution in Laminated Composites
,”
IUTAM Symposium on Inelastic Deformation of Composite Materials
,
1990
, pp.
549
-
561
.
17.
Harris
,
C. E.
and
Allen
,
D. H.
, “
A Continuum Damage Model of Fatigue-Induced Damage in Laminated Composites
,”
SAMPE Journal
, July/Aug. 1988, pp.
43
-
51
.
18.
Lo
,
D. C.
,
Coats
,
T. W.
,
Harris
,
C. E.
, and
Allen
,
D. H.
, “
PDALC User’s Manual, Version 1.0, Progressive Damage Analysis of Laminated Composites (PDALC) (A Computational Model Implemented in the NASA COMET Finite Element Code
,”
NAS-A Technical Memorandum
 4724,
NASA LaRC
,
1996
.
19.
Lo
,
D. C.
,
Allen
,
D. H.
, and
Harris
,
C. E.
, “
A Procedure for Utilization of a Damage-Dependent Constitutive Model for Laminated Composities
,”
NASA Technical Memorandum
 104219,
NASA LaRC
,
1992
.
20.
Coats
,
T. W.
, “
Experimental Verification of a Progressive Damage Model for Composite Laminates Utilizing Continuum Damage Mechanics
,” Master’s Thesis,
Old Dominion University
,
12
1992
.
21.
O’Brien
,
T. K.
, “
Analysis of Local Delamination and Their Influence on Composite Laminate Behavior
,”
Delamination and Debonding of Materials
, ASTM STP 876,
American Society for Testing and Materials
,
West Conshohocken, PA
,
1985
, pp.
282
-
297
.
This content is only available via PDF.
You do not currently have access to this content.