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Mechanics of Composite Materials

, Volume 44, Issue 3, pp 279–288 | Cite as

Strengthening of RC beams with an innovative timber-FRP composite system

  • N. Mazzon
  • M. Guadagnini
  • M. R. Valluzzi
Article

Abstract

The results of a theoretical and experimental research project on the use of an innovative technique for strengthening concrete beams are presented. A spacer element is inserted between the tension side of a beam and the composite material to increase its lever arm and to enhance the over all stiffness of the strengthened beam. The main aim of this exploratory project was to increase the ultimate failure load of strengthened beam specimens, whilst guaranteeing acceptable over all deflections at the serviceability limit states. This resulted into a significant reduction in the amount of FPR required and in a better utilization of the materials employed. A preliminary theoretical study was carried out to investigate the effect of Young’s modulus, failure strain, and thickness of the element to be used as a spacer in order to determine the best possible candidate material. Three tests on 2.5-m-long beams were carried out, and different anchorage techniques were used to try and prevent the debonding of the strengthening system. The results from this pilot study are very promising, as the strengthening system ensures an adequate initial stiffness along with an improved ultimate flexural capacity.

Keywords

beam FRP timber strengthening serviceability limit state deflection crack width flexural behaviour 

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Copyright information

© Springer Science+Business Media, Inc. 2008

Authors and Affiliations

  • N. Mazzon
    • 1
  • M. Guadagnini
    • 2
  • M. R. Valluzzi
    • 1
  1. 1.Department of Civil EngineeringUniversity of PaduaPaduaItaly
  2. 2.Department of Civil and Structural EngineeringUniversity of SheffieldSheffield, South YorkshireUK

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