This article focuses on the development and application of a 3 * 3 coupler-based Mach-Zehnder interferometer. The software for signal demodulation is developed. Based on waveforms obtained at intermediate steps, plausible errors are analyzed and found to be small. The interferometer is then applied to the delamination detection in fiber-reinforced polymer (FRP) composites. Test results indicate the feasibility of detecting both the size and location of delamination by applying quasi-impulse loadings.
Brown, D.A., Cameron, C.B., Keolian, R.M., Gardner, D.L. and Garrett, S.L.1991. "A Symmetric 3x3 Coupler Based Demodulator for Fiber Optic Interferometric Sensors," SPIE, 1584:328-335.
2.
Choi, H.Y. and Chang, F.-K.1992. "Model for Predicting Damage in Graphite/Epoxy Laminated Composites Resulting from Low-Velocity Point Impact," Journal of Composite Materials, 26: 2134-2169.
3.
Elvin, N., Leung C.K.Y., Sudarshanam, V.S. and Ezekiel, S.1990. "A Novel Fiber Optic Delamination Detection Scheme: Theoretical and Experimental Feasibility Studies," Journal of Intelligent Material, Systems & Structures, 10(4): 314-321.
4.
Geubelle, P.H. and Baylor, J.S.1998. "Impact-Induced Delamination of Composites: A 2D Simulation ," Composites Part B: Engineering, 29(5):589-602.
Khuri-Yakub, B.T., Degertekin, F.L. and Pei, J.1997. "Dry Contact Ultrasonic Sensors for Structural Monitoring ," In: Chang, F-K. (ed.), Structural Health Monitoring: Current Status and Perspectives , pp. 481-491.
7.
Lahiri J., Siddalingaiah D.L., Kamaraguru P.P. and Reddy K.S.1992. "Non-Destructive Evaluation of Delaminations and Voids in Axi-Symmetric CFRP Shells: Part A Scope and Limitation of X-ray Radiography ," In: Hallai, C. and Kulcsar, P. (eds), Non-Destructive Testing 92, Elsevier, New York, pp. 625-631.
8.
Liu, K. and Measures, R.M.1992. "Singnal Processing Techniques for Interferometric Fiber-Optic Strain Sensors," J. Intel. Meter. Syst. Struct. , 3:432-461.
