An Experimental Investigation on Pull-Off Tests Conducted on FRP Composites Applied to Brick Units

Abstract:

In the present study, a series of pull-off tests is performed to determine the bonding properties of fiber reinforced polymer (FRP) composites applied to a brittle substrate. Pull-off test is simple, fast and cheap and it is generally employed to evaluate the bond strength between the composite and the substrate. It is a procedure that can be easily performed on-site for checking the quality of the reinforcement adhesion.A steel composite made of a unidirectional steel fabric embedded in an organic matrix (bi-component epoxy resin) was applied to the surface of fired-clay bricks. A shallow core perpendicular to the surface was realized in the test specimen, leaving the core attached to the brick. A steel dolly was glued to the external surface of the core using epoxy adhesive. A loading device was employed to apply the tensile force until failure. The effects of moisture presence on the substrate and shape of the cores on the pull-off strength were investigated.

• Periodical: Key Engineering Materials (Volume 817)
• Pages: 421-426
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.817.421
• Online since: August 2019
• Authors: Mahdi Ghaemi, Angelo Di Tommaso, Cristina Gentilini*
• Keywords: Bond, Composites, Masonry, Pull-Off Test, SRP

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