Materials and Structures

, Volume 32, Issue 2, pp 140–143 | Cite as

Assessment of glass fibre reinforced cement byin-situ SEM bending test

  • P. Trtik
  • P. J. M. Bartos
Technical Reports

Abstract

The purpose, development and the first results of a new test method, an SEMin-situ 3-point flexural test are presented. A large SEM chamber housing a eucentric tensile testing rig has been redesigned and fitted with a new apparatus enabling microfracture processes in bending to be simultaneously scanned and the corresponding load/deflection and other data and parameters accurately recorded. The new test facility provides an opportunity to obtain new quantitative and qualitative data considerably more relevant to the fracture processes concerned than those obtained when previous SEMin-situ tests are used. It is now possible to examine specimens of a more realistic size and including different types of reinforcement in bending, a very common and practical mode of loading. The new test method has been initially applied to an investigation of fracture mechanism in glass fibre reinforced cement (GRC) where the results have shown major differences between flexural performance of aged and unaged GRC. Thein-situ SEM flexural test offers an effective new tool for the investigation of the complex micro-fracture mechanics of fibre reinforced composites as represented by cement reinforced with bundles of glass fibres.

Keywords

Steel Fibre Realistic Size Cement Base Composite Practical Mode Reinforce Cement Composite 

Résumé

Cette étude présente le développement et les premiers résultats d’une nouvelle méthode d’essai par un microscope électronique au scanner utilisant 3 points de flexion. L’équipement de la chambre large d’essai de traction par flexion a été modifié et ajusté avec un nouvel appareil favorisant le processus de la microrupture. Ce dernier permet simultanément de scanner et d’enregistrer la charge-déformation ainsi que d’autres paramètres avec une bonne précision. L’équipement du nouvel essai permet d’obtenir d’avantages de nouvelles données relatives au processus de rupture qu’avec l’ancien microscope électronique au scanner. Il est maintenant possible d’examiner les échantillons ayant des dimensions réalistes et incluant différents type de renforcement et de modes communs et pratiques de chargement. La nouvelle méthode d’essai a été utilisée dans l’étude du mécanisme de la rupture des composites ciment-fibres de verre (CCV) où les résultats ont montré des différences majeures entre les performances de la flexion des échantillons en vieillissement normal et accéléré. L’essai de flexionin-situ du microscope électronique avec scanner offre un outil efficace pour l’étude de la mécanique de la microrupture des composites, tels les composites ciment-fibres de verre.

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References

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Copyright information

© RILEM 1999

Authors and Affiliations

  • P. Trtik
    • 1
  • P. J. M. Bartos
    • 1
  1. 1.Advanced Concrete and Masonry CentreUniversity of PaisleyPaisleyUK

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