Factors influencing bond of CFRP to steel

Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review

Abstract

Many infrastructures require structural strengthening, e.g. (Miller et al., 2001; Libby and Mullins, 2001; Bank, 2006; Kirk and Mallet, 2007), and the use of fiber reinforced polymers on that endeavor has been growing in spite of uncertainties related to their lifetime behavior. Premature debonding of external strengthening under adverse environmental conditions is a major source of concern, including in the case of carbon fiber reinforced polymers (CFRP) used in the strengthening of steel structures, namely bridges. Failure of those CFRP-steel structural members may occur at the joints and this study examines factors that alter or explain reduction of the load capacity of the latter, namely surface treatment prior to bonding, the glass transition temperature (Tg) of the adhesive, the exposure to freeze-thaw (FT) cycles, that artificially accelerate aging of the components, and the effects of temperature nearing Tg on the mechanical strength of the joints. An experimental program was undertaken to analyze the influence of these factors on the performance of the joints. The steel surface was subjected to sand blasting (6.3bar), abrasive grinding (6.9bar) Sa 2, to compare with no treatment, and the case of rust induced by 10 days exposure to salt fog was also considered. Tests made at different temperatures allowed comparison of ultimate capacities of strains and failure modes, Table 1, confirming rapid deterioration. The quantification of the losses of mechanical resistance was made essentially by shear tests of double strap specimens. Changes of bond-slip responses with increasing operational temperature up to and above adhesive Tg were significant. Preparation of surface by sand blasting was found more effective than by grit steel blasting, but further tests are needed to ascertain that degrees of treatment neared optimum roughness in each case. Adhesion failures after FT were analyzed and compared with evolution of Tg showing negligible changes, in general. Scanning electronic microscope images were used to help interpret results. However, elemental component changes obtained by EDS at selected spots were found inconclusive.
Original languageEnglish
Title of host publication9th International Conference on Fibre-Reinforced Polymer (FRP) Composites in Civil Engineering, CICE 2018
EditorsEmmanuel Ferrier, Karim Benzarti, Jean-Francois Caron
PublisherInternational Institute for FRP in Construction (IIFC)
Pages231-238
Number of pages8
ISBN (Electronic)978-000000000-2
Publication statusPublished - 2018
Event9th International Conference on Fibre-Reinforced Polymer (FRP) Composites in Civil Engineering, CICE 2018 - Paris, France
Duration: 17 Jul 201819 Jul 2018

Publication series

NameInternational Conference on Fibre-Reinforced Polymer (FRP) Composites in Civil Engineering
Volume2018-July

Conference

Conference9th International Conference on Fibre-Reinforced Polymer (FRP) Composites in Civil Engineering, CICE 2018
Country/TerritoryFrance
CityParis
Period17/07/1819/07/18

Keywords

  • Bond and interfacial stresses
  • Characterization of FRP
  • Experimental study
  • FRC materials/systems
  • Strengthening and repair

Fingerprint

Dive into the research topics of 'Factors influencing bond of CFRP to steel'. Together they form a unique fingerprint.

Cite this