Analysis of the mechanical behavior of composite T-joints reinforced by one side stitching

Analysis of the mechanical behavior of composite T-joints reinforced by one side stitching T-joints stiffeners made from carbon/epoxy composites have been increasingly applied in aeronautical structures, however as majority of the carbon fiber reinforced structures, they have faced with delamination problems. Through-the-thickness reinforcements for laminate composites have been studied as manner to increase transversal strength, especially reducing delamination. In the present work, carbon/epoxy T-joints reinforced transversally by one side stitching (OSS) and molded on Resin Transfer Molding (RTM) process have been performed as well as the reference (unstitched T-joints). The stitching position were designed after analysis of the unstitched T-joints by means of strain field on Digital Image Correlation (DIC) under pull-off test to better improve the areas submitted to large strain. Also, the stitched samples were mechanically tested in pull-off mode and were analyzed during tests by in situ microscopy and post-failure on Scanning Electron Microscopy .The energy release was better contained in the stitched structures especially in the critical region (delta-fillet), due to crack bridging that improved the delamination toughness. Otherwise, the stitch pattern generated by OSS process changed the strain fields asymmetrically when analyzed on DIC during tests. The stitched T-joints showed greater ultimate strength (25%) and load recovery post ultimate strength (19%) in comparison to the reference. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Composite Structures Elsevier

Analysis of the mechanical behavior of composite T-joints reinforced by one side stitching

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Publisher
Elsevier
Copyright
Copyright © 2017 Elsevier Ltd
ISSN
0263-8223
eISSN
1879-1085
DOI
10.1016/j.compstruct.2017.06.041
Publisher site
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Abstract

T-joints stiffeners made from carbon/epoxy composites have been increasingly applied in aeronautical structures, however as majority of the carbon fiber reinforced structures, they have faced with delamination problems. Through-the-thickness reinforcements for laminate composites have been studied as manner to increase transversal strength, especially reducing delamination. In the present work, carbon/epoxy T-joints reinforced transversally by one side stitching (OSS) and molded on Resin Transfer Molding (RTM) process have been performed as well as the reference (unstitched T-joints). The stitching position were designed after analysis of the unstitched T-joints by means of strain field on Digital Image Correlation (DIC) under pull-off test to better improve the areas submitted to large strain. Also, the stitched samples were mechanically tested in pull-off mode and were analyzed during tests by in situ microscopy and post-failure on Scanning Electron Microscopy .The energy release was better contained in the stitched structures especially in the critical region (delta-fillet), due to crack bridging that improved the delamination toughness. Otherwise, the stitch pattern generated by OSS process changed the strain fields asymmetrically when analyzed on DIC during tests. The stitched T-joints showed greater ultimate strength (25%) and load recovery post ultimate strength (19%) in comparison to the reference.

Journal

Composite Structures – Elsevier

Published: Jan 15, 2018

References

  • Fatigue life of a carbon fiber composite T-joint under a standard fighter aircraft spectrum load sequence
    Thawre, M.; Pandey, K.; Dubey, A.; Verma, K.; Peshwe, D.; Parandkar, R.
  • Strengthening of composite T-joints using novel ply design approaches
    Burns, L.; Mouritz, A.P.; Pook, D.; Feih, S.
  • Bio-inspired hierarchical design of composite T-joints with improved structural properties
    Burns, L.; Mouritz, A.P.; Pook, D.; Feih, S.
  • Testing and analysis of ultra thick composite
    Zimmermann, K.; Zenkert, D.; Siemandzki, M.
  • Strength improvement to composite T-joints under bending through bio-inspired design
    Burns, L.A.; Mouritz, A.P.; Pook, D.; Feih, S.
  • The assessment of novel materials and processes for the impact tolerant design of stiffened composite aerospace structures
    Greenhalgh, E.; Hiley, M.
  • Design in nature: learning from trees
    Mattheck, C.
  • Dissimilar material joints with and without free-edge stress singularities: Part I. A biologically inspired design
    Xu, L.; Kuai, H.; Sengupta, S.
  • Bio-inspired design of aerospace composite joints for improved damage tolerance
    Burns, L.A.; Mouritz, A.P.; Pook, D.; Feih, S.
  • Delamination resistant laminates by Z-Fiber® pinning. Part I Manufacture and fracture performance
    Partridge, I.; Cartié, D.
  • Mixed mode delamination of polymer composite laminates reinforced through the thickness by z-fiber
    Rugg, K.L.; Cox, B.N.; Massabo, R.
  • Strengthening mechanics of thin and thick composite T-joints reinforced with z-pins
    Koh, T.M.; Feih, S.; Mouritz, A.P.
  • Recent development in the robotic stitching technology for textile structural composites
    Wittig, J.
  • Experimental and numerical analysis of transverse stitched T-joints in bending
    Stickler, P.B.; Ramulu, M.; Johnson, P.S.
  • 3D reinforcement of stiffener-to-skin T-joints by Z-pinning and tufting
    Cartié, D.D.; Dell’Anno, G.; Poulin, E.; Partridge, I.K.
  • On the effects of stitching in CFRPs—I. Mode I delamination toughness
    Dransfield, K.A.; Jain, L.K.; Mai, Y.W.
  • Mode II delamination toughness of stitched graphite/epoxy textile composites
    Sankar, B.V.; Sharma, S.K.
  • Improving the delamination resistance of CFRP by stitching—a review
    Dransfield, K.; Baillie, C.; Mai, Y.W.
  • Dandermination of mode II delamination toughness of stitched laminated composites
    Jain, L.K.; Mai, Y.W.
  • Impact properties of laminated composites with stitching fibers
    Byun, J.H.; Song, S.W.; Lee, C.H.; Um, M.K.; Hwang, B.S.
  • Further validation of the Jain and Mai models for interlaminar fracture of stitched composites
    Mouritz, A.P.; Jain, L.K.
  • Delamination-Debond Behaviour of Composite T-Joints in Wind Turbine Blades
    Gulasik, X.H.; Coker, D.
  • Analysis of composite T-joint designs for enhanced resistance to hydrodynamic ram
    May, M.; Ganzenmüller, G.; Wolfrum, J.; Heimbs, S.
  • Damage tolerance of laminated tee joints in FRP structures
    Phillips, H.J.; Shenoi, R.A.
  • Evaluation of toughening concepts at structural features in CFRP—Part I: Stiffener pull-off
    Greenhalgh, E.; Lewis, A.; Bowen, R.; Grassi, M.
  • Failure analysis and strengthening mechanism of Z-pinned composite T-joints under tensile loading
    Tan, Y.; Li, Y.; Huan, D.; Zhang, X.; Chu, Q.
  • Hydrodynamic ram analysis of aircraft fuel tank with different composite T-joint designs
    Heimbs, S.; Duwensee, T.; Nogueira, A.C.; Wolfrum, J.
  • Static pull and push bending properties of RTM-made TWF composite tee-joints
    Chuyang, L.U.O.; Xiong, J.
  • The effect of stitch incline angle on mode I fracture toughness–Experimental and modelling
    Plain, K.P.; Tong, L.
  • Influence of loading rate on the delamination response of untufted and tufted carbon epoxy non-crimp fabric composites/Mode II
    Colin de Verdiere, M.; Skordos, A.A.; Walton, A.C.; May, M.
  • Mode I interlaminar fracture toughness properties of advanced textile fibreglass composites
    Mouritz, A.P.; Baini, C.; Herszberg, I.

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