The effect of surface treatment and environmental actions on the adhesive connection between GFRP laminate surface and fresh FRC

An experimental study on the performance of adhesive connection between Glass Fibre Reinforced Polymer (GFRP) plates and Steel Fibre reinforced self-compacting Concrete (FRC) was conducted. Fresh FRC was poured out onto the surface of GFPR plates, to create 40 square specimens (300 by 300 by 45 [mm]). Pull-off tests were performed to evaluate the tensile strength of the adhesive connection when different types of adhesives (four) and surface treatments (three) are used. Furthermore, the effect of five different environmental conditions on the tensile strength of the adhesive connection was also evaluated. After analysing the results and performing a variance analysis (ANOVA), it has been shown that the pull-off behaviour is highly influenced by the type of adhesive and by the environmental action. In spite of that, the dominant failure mode was cohesive failure in the FRC substrate, therefore good bond conditions between both materials were achieved.POCI-01-0247-FEDER-003480; SFRH/BSAB/150266/2019; SIKA, KERAKOLL and MAPEI. project “EasyFloor – Development of composite sandwich panels for rehabilitation of floor buildings”, involving the company ALTO – Perfis Pultrudidos, Lda., ISISE/University of Minho and CERis/Instituto Superior Técnico, supported by FEDER funds through the Operational Program for Operational Program for Competitiveness and Internationalization (POCI) and the Portuguese National Innovation Agency (ANI) – project no. 3480 (POCI-01-0247-FEDER-003480). The first author acknowledges the grant SFRH/BSAB/150266/2019 provided by FCT, financed by European Social Fund and by national funds through the FCT/MCTES. Acknowledgments are extended to LEST – Laboratório de Estruturas for their material support. The authors would like to thank SIKA, KERAKOLL and MAPEI companies for suppling the adhesive