Numerical and Experimental Failure Analysis of Composite Laminates with Bolted Joints under Bending Loads

Abstract

A three-dimensional contact mechanics analysis has been successfully made on the composite laminates with bolted joints under bending loads. The AS4/3501-6 laminates of [0₈/90₈]_s and [90₈/0₈]_s lay-up with two types of countersunk bolted joints, MS-24UNF-3A (ψ = 80°) and NAS-24UNJF-3A (ψ = 100°), subjected to bending loads are analyzed, respectively. The effects of friction, stacking sequence and countersunk bolt head on the contact tractions around the bolted joint are studied systematically. The progressive failure analysis based on the maximum stress theory, Ye delamination criterion and the complete ply failure approach is performed for predicting the maximum bending load that the laminate can sustain before it catastrophically fails. Toward this end, experimental tests were also conducted to measure the maximum bending load for the laminates with the countersunk bolted joints under bending loads. From the results, it is shown that the joint configuration of [90₈/0₈]_s laminate and NAS-24UNJF-3A (ψ = 100°) countersunk bolt has more higher bending strength while the joint configuration of [0₈/90₈]_s laminate and NAS-24UNJF-3A (ψ = 100°) countersunk bolt has more higher bending stiffness. Good agreement between the computed and experimental results shows the applicability of the technique developed. The present work should be of help for the design of composite laminates with the countersunk bolted joints.

Keywords

composite laminates bolted joint failure analysis delamination contacttraction bending loads

Get full access to this article

View all access options for this article.

References

1. SFSM-400 . 1972. Standard Fastener Systems Manual. Santa Ana, CA: Advanced Structures & Technology Co., B-3-1.

2. ANSI . 1970. Fastener Standards, Fifth Edition. Cleveland, OH: Industrial Fasteners Institute, B18.6.4.

3. Collings, T. A. 1987. "Experimentally Determined Strength of Mechanically Fastened Joints," in Joining Fibre-Reinforced Plastics, F. L. Matthews , ed., England: Elsevier Applied Science Publishers LTD, pp. 9-63.

4. Godwin, E. W. and F. L. Matthews . 1980. "A Review of the Strength of Joints in Fibre-Reinforced Plastics: Part 1. Mechanically Fastened Joints," Composites, pp. 155-160.

5. Marshall, I. H. , W. S. Arnold , J. Wood and R. F. Mousley . 1989. "Observations on Bolted Connections in Composite Structures," Composite Structures, 13:133-151.

6. Lee, Y. J. and W. H. Chen . 1991. "Study on the Failure Behavior of Bolted Connections in Vessel Made of GFRP Laminates." Journal of The Society of Naval Achitects of Japan, 169:467-476.

7. Delale, F. , N. N. Kishore and A. S. D. Wang . 1984. "Stress Analysis of a Composite Plate with a Circular Hole under Axisymmetric Bending," Journal of Composite Materials, 18:420-431.

8. Prasad, C. B. and M. J. Shuart . 1990. "Moment Distributions around Holes in Symmetric Composite Laminates Subjected to Bending Moments," AIAA Journal, 28(5):877-882.

9. Tsai, P. and W. H. Chen . 1986. "Finite Element Analysis of Elastodynamic Sliding Contact Problems with Friction," Computer & Structures, 22:925-938.

10.

10. Chen, W. H. and J. T. Yeh . 1988. "Finite Element Analysis of Finite Deformation Contact Problems with Friction," Computers & Structures, 29:423-436.

11.

11. Chen, W. H. and J. T. Yeh . 1990. "Three-Dimensional Finite Element Analysis of Static and Dynamic Contact Problems with Friction," Computers & Structures, 35:541-552.

12.

12. Hahn, H. T. and S. W. Tsai . 1974. "On the Behavior of Composite Laminates after Initial Failures," Journal of Composite Materials, 8:288-305.

13.

13. Lee, J. D. 1982. "Three Dimensional Finite Element Analysis of Damage Accumulation in Composite Laminate," Computers & Structures, 15(3):335-350.

14.

14. Chang, F. K. and K. Y. Chang . 1987. "A Progressive Damage Model for Laminated Composites Containing Stress Concentrations," Journal of Composite Materials, 21:834-855.

15.

15. Datoo, M. H. 1991. Mechanics of Fibrous Composites. New York, NY: Elsevier Science Publishing Co., Inc.

16.

16. Ye, L. 1988. "Role of Matrix Resin in Delamination Onset and Growth in Composite Laminates,; Composite Science and Technology, 33:257-277.

17.

17. MIL-HDBK-SB . 1971. Metallic Material and Elements for Aerospace Vehicle Structures. Washington, D.C.: U.S. Government Printing Office.

18.

18. Reddy, J. N. and A. K. Pandey . 1987. "A First-Ply Failure Analysis of Composite Laminates," Computers & Structures, 25:371-393.