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Abstract

Dynamic modeling of interfacial cracks between the skin and core materials was performed and numerical simulation was undertaken to study the feasibility of crack detection. The cracks were modeled in the way as they were physically in the sandwich beam structures using the finite element method. Numerical simulation of impact-hammer hit was applied to the finite element models to calculate the time history of strain responses along the sandwich beams. Dynamic crack opening and closure was considered with friction at the surfaces of interfacial cracks. Thus, nonlinear dynamic analysis was conducted. Then, the Fast Fourier Transform (FFT) was used to transform the time responses to frequency responses. The effects of interfacial cracks were examined in both time and frequency plots by comparing those responses between the damaged structure and the intact structure. The present study showed that the effect of crack closure was important so that nonlinear analysis was necessary to represent the interfacial crack behaviors properly. The strain response from nonlinear dynamic analysis (i.e. simulated impact hammer hit) had great potential for detecting and locating a small size of interfacial crack in a sandwich beam structure.

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References

1. Helnicki, A.J. , Attain, A.E. , Comfort, L.K. and Kam, M. (1997). Information technology in civil infrastructure system monitoring: opportunities and issues. In: Proceedings of the 1st International Workshop on Structural Health Monitoring: Current Status and Perspectives. Chang, F.-K. (ed.), Lancaster PA: Technomic Publishing Company, pp. 396-409.

2. Doebling, S.W. , Farrar, C.R. , Prime, M.B. and Shevitz, D.W. (1996). Damage Identification and Health Monitoring of Structural and Mechanical Systems from Changes in Their Vibration Characteristics: A Literature Review, Los Alamos National Laboratory Report LA-13070- MS, Los Alamos, New Mexico.

3. Chang, F.-K. (ed.) (1997). Structural Health Monitoring: A summary Report on the First International Workshop on Structural Health Monitoring. Lancaster PA: Technomic Publishing Company.

4. Chang, F.-K. (ed.) (1999). In: Proceedings of the 2nd International Workshop on Structural Health Monitoring: Current Status and Perspectives. Technomic Publishing Company, Lancaster PA.

5. Spyrakos, C. , Chen, H.L. , Stephens, J. and Govidara, V. (1990). Evaluating structural deterioration using dynamic response characterization. In: Proc. Intelligent Structures. Elsevier Applied Science. pp. 137-154.

6. Rehm, G. (1987). Nondestructive tests for early damage detection. In: Proc. US-European Workshop on Bridge Evaluation, Repair, and Rehabilitation. St. Remy-Les-Chevreuse.

7. Yuen, M.M.F. (1985). A numerical study of eigenparameters of a damaged cantilever. Journal of Sound and Vibration, 103: 301-310.

8. Adams, R.D. , Cawley, P. , Pye, C.J. and Stone, B.J. (1978). A vibration technique for non-destructively assessing the integrity of structures. Journal of Mechanical Engineering Sciences, 20: 93-100.

9. Pandey, A.K. and Biswas, M. (1994). Damage detection in structures using changes in flexibility. Journal of Sound and Vibration, 169(1): 3-17.

10.

10. Lipsey, S.A. and Kwon, Y.W. (1999). Numerical study for global detection of cracks embedded in beams. In: Kwon, Y.W. and Chung, H.H. (eds.), Recent Advances in Solids and Structures-1999. ASME PVP-Vol. 398, pp. 69-75.

11.

11. Owen, D.R.J. and Li, Z.H. (1987). A refined analysis of laminated plates by finite element displacement methods - I. Fundamental and static analysis. Computers and Structures, 26(6): 907-914.

12.

12. Kwon, Y.W. and Bang, H. (2000). The Finite Element Method Using MATLAB, 2nd Edn., Boca Raton, Florida: CRC Press.

13.

13. Hughes, T.R.J. , Taylor, R.L. , Sackman, J.L. , Curnier, A. and Kanoknukulchai, W. (1976). A finite element method for a class of contact-impact problems. Compu. Meth. Appl. Mech. Engng., 8: 249-276.

Dynamic Numerical Modeling and Simulation of Interfacial Cracks in Sandwich Structures for Damage Detection

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