Effect of aggregate size on bond behaviour between basalt fibre reinforced polymer sheets and concrete

Abstract

The effect of aggregate size on the interfacial bond behaviour between BFRP sheets and concrete is investigated in this study by conducting single-lap shear tests. The effect of aggregate sizes (i.e. 5–10 mm, 10–15 mm, and 15–20 mm) on the debonding load, maximum bond stress, effective bond length, local slip at peak shear stress, as well as the bond-slip relationship between the BFRP sheets and concrete are presented and discussed. The experimental results have shown a significant effect of the aggregate size on the interfacial bond-slip behaviour. The interfacial shear stress decreased when the aggregate size increased due to the decreased tensile strength of concrete. The relative slip between BFRP and concrete at the peak bond stress increased with the increasing aggregate size also because of the reduced tensile strength of concrete. Existing models regarding the bond strength and interfacial bond-slip are adopted and recalibrated against the experimental results in which the size effect of aggregates is incorporated.