In Situ Evaluation of 3-D Woven Composite Structural Performance Using Fiber Optic Sensors
Abstract
Report developed under STTR contract for topic AFOOT-0022 describes scientific approaches, engineering solutions and practical results of in situ strain monitoring in 3-D woven composite materials, their bonded and bolted joints using integrated networks of Bragg grating fiber optic sensors. A number of continuous optical fibers carrying hundreds of sensors were integrated into 3-D weaving process simultaneous with the host warp, fill and Z-yarns, and thus became an integral part of produced 3-D woven preform The preform was then consolidate using VARTM process and provided experimental flat coupons for tensile and flexural testing. The same fiber optics instrumented material was used for fabrication of double-lap bonded and bolted joint elements, which were exposed to uniaxial tensile tests. Experimental results showed capability of the integrated fiber optic sensors to monitor internal strain fields and adequately respond to strain concentration caused by cutouts, bolts and overlap ends. Experimental strain field results obtained from integrated fiber optic sensors were compared with foil gage and Moire interferometry data, as well as with finite element analysis results and showed good agreement. A practical Cut and Polish method of connecting ends of integrated optical fibers to the data acquisition system was developed and validated.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 28, 2005
- Accession Number
- ADA431092
Entities
People
- Alexander E. Bogdanovich
- Don Wigent
- Thomas J. Whitney
- Thomas Wavering