Performance of externally bonded GFRP sheets on concrete in tropical environments. Part I: Structural scale tests

A set of accelerated aging and natural environment tests has been carried out to evaluate performance of glass fibres reinforced polymer (GFRP) sheets bonded on concrete in tropical environment. Plain concrete beams were cast and externally reinforced by bonding with E-glass GFRP sheets. The beams were immersed in a 60 °C water bath for varying durations. The novelty of the experiment was that the environmental exposure was given while they were subjected to service loads. This load helped in keeping sheet exposed to hot water under stressed condition. Thus field environment very similar to tropical climate was simulated. The loaded specimens were also subjected to natural weathering for 6 and 12 months duration. The sheets were removed from the specimens and the tensile strength and modulus were determined to assess the degradation, if any. In the first part of the paper the structural level studies are discussed. In Part 2 the microstructural investigation is reported.