In-Situ Strain Monitoring in Deltoid of Composite T-joints using Optical Fiber

In-Situ Strain Monitoring in Deltoid of Composite T-joints using Optical Fiber

Shinsaku Hisada, Shu Minakuchi, Nobuo Takeda

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Abstract. Composite T-joints have a critical problem that cracks occur in the deltoid during curing because of the cure stress and thermal stress. There are few studies on the behavior of T-joints during curing, and what is actually occurring in the deltoid is not well understood. In the present study, optical fiber was embedded in the deltoid using a new technique to clarify the internal state of the deltoid during curing. The embedded optical fiber successfully measured the process-induced strain distribution in the deltoid. Based on the experimental results and finite element analysis, a failure index for a process-induced failure of deltoid was discussed. An energy-based failure index could precisely predict the process-induced failure.

Optical Fiber, T-joint, Deltoid, Process Monitoring

Published online 2/20/2021, 9 pages
Copyright © 2021 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: Shinsaku Hisada, Shu Minakuchi, Nobuo Takeda, In-Situ Strain Monitoring in Deltoid of Composite T-joints using Optical Fiber, Materials Research Proceedings, Vol. 18, pp 161-169, 2021


The article was published as article 19 of the book Structural Health Monitoring

Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

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