Materials and Structures

, Volume 33, Issue 8, pp 515–524 | Cite as

Parameters related to fiber length and processing in cementitious composites

  • Y. Akkaya
  • A. Peled
  • S. P. Shah
Technical Reports

Abstract

Effects of fiber length on the tensile and flexural performance of cast and extruded PVA fiber reinforced cement composites were investigated. Microstructural characterization, image analysis, and statistical tools were used to study the influence of processing and fiber length on fiber-matrix bond, fiber dispersion and fiber orientation in the composites. In the extruded composites, shorter fibers improved the performance. In the cast composites, longer fibers gave the best performance. This contradictory trend was found to be a result of differences in fiber failure mechanism, fiber distribution and fiber orientation. Microstructural observations indicated a strong matrix-fiber bond for the extruded composites. Statistical quantification of image analysis indicated a better distribution and alignment of shorter fibers in extruded composites.

Keywords

Fiber Length Fiber Orientation Fiber Composite Short Fiber Critical Length 

Résumé

Les effets de la longueur des fibres sur les performances de tension et de flexion des composites moulés et des composites extrudés, à base de ciment renforcé et de fibres d’acétate de polyvinyle, ont été étudiés. La caractérisation microstructurale, l’analyse d’images et des outils statistiques ont été utilisés pour étudier l’influence du traitement et de la longueur des fibres sur le lien fibres-matrices, la dispersion et l’orientation des fibres dans les composites. Dans les composites extrudés, des fibres plus courtes ont amélioré les performances. Dans les composites moulés, des fibres plus longues ont engendré de meilleures performances. Cette tendance contradictoire s’est avérée être le résultat de différences dans le mécanisme de rupture des fibres, la distribution des fibres et l’orientation des fibres. Les observations microstructurales ont indiqué un lien matrice-fibres important pour les composites expulsés. La quantification statistique de l’analyse d’images a montré une meilleure répartition et un meilleur alignement des fibres plus courtes dans les composites extrudés.

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Copyright information

© RILEM 2000

Authors and Affiliations

  • Y. Akkaya
    • 1
  • A. Peled
    • 1
  • S. P. Shah
    • 1
  1. 1.Department of Civil EngineeringNorthwestern UniversityEvanstonUSA

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