Experimental Mechanics

, 49:877 | Cite as

Measuring Strains through the Thickness of a Composite Structural Specimen Subjected to Bending

  • M. Mulle
  • R. Zitoune
  • F. Collombet
  • L. Robert
  • Y.-H. Grunevald


This study concerns the central reinforced zone of a composite structural specimen. In order to estimate the strain distribution during a series of three and four-point bending tests, several optical fiber Bragg grating sensors have been embedded in various levels of the ply stack. Simultaneously, surface strain field measurements by 3-D digital image correlation are undertaken. Both techniques show a general linear distribution of longitudinal strains through the thickness of the thick zone but values are slightly different. A numerical model is developed and a test-calculation dialogue is carried out. The complementary information given by the two optical techniques for in-core and surface measurements reveals the importance of considering structural and edge effects.


Composites Fiber Bragg gratings 3-D digital image correlation Finite element analysis Bending tests 


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Copyright information

© Society for Experimental Mechanics 2008

Authors and Affiliations

  • M. Mulle
    • 1
  • R. Zitoune
    • 1
  • F. Collombet
    • 1
  • L. Robert
    • 2
  • Y.-H. Grunevald
    • 3
  1. 1.Laboratoire de Génie Mécanique de Toulouse (LGMT)University of Toulouse, INSA, UPSToulouseFrance
  2. 2.CROMeP, Ecole Mines AlbiAlbi CT Cedex 09France
  3. 3.DDL Consultants, Pas de PouyenLe BeaussetFrance

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