Improvement of the FRP sheet bonded to concrete substrate by silane coupling agent

Abstract

We experimentally studied the fine lightweight aggregate with the particle size range of 3.15-4.75 mm used as functional bridge between FRP sheet and concrete substrate. However, problems would appear and how to deal with the interfacial transition zone (ITZ) and make it stronger is the key point for this concept. Considering that silane coupling agent (SCA) can provide a better bond on a silicon-containing material surface, it was introduced as a modifying material to further improve the bond quality of the ITZ between lightweight aggregate and cement paste. Results indicated that the water absorptivity of lightweight aggregate can be controlled by SCA solutions, and the pull-off bond strength, mechanical strength, and microhardness were increased, which was attributed to the optimized microstructure under the condition of an appropriate concentration of SCA.

Keywords

lightweight aggregate / silane coupling agent / interfacial transition zone / FRP sheet

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