Co-authors​ :

 Meiran ABDO (UNITED KINGDOM), Eleni TOUMPANAKI , Andrea DIAMBRA , Lawrence BANK  

The application of fibre-reinforced polymer (FRP) composites has substantially increased in recent years. Currently, the reuse and/or recycling of composite waste is minimal, with most waste being disposed of in landfills or incinerated. Recently, mechanical recycling and pyrolysis have been developed to recycle FRP composites, but they have yet to be fully commercialised (Tao, et al., 2023). As an alternative recycling strategy, incorporating glass fibre-reinforced polymer (GFRP) into concrete has shown significant potential from both economic and environmental perspectives (Ribeiro, et al., 2023). This study introduces a new type of discrete reinforcing elements for concrete produced from wind-blade waste (FRP) composite materials, defined as FRP needles. The bond integrity between the FRP needles and concrete dictates the mechanical performance of the composite system, and it is crucial for post-failure strength retention and cracks bridging effect. The bond performance between commercial GFRP bars and concrete is achieved through their sand coating layer and surface deformations. However, in this study, the cutting process results in a smooth surface on the FRP needles. Sand and glass blasting techniques have been employed to create a rougher surface to address this issue. The surface roughness was measured using an Alicona microscope machine.
The experimental procedure utilised pull-out testing of 10 specimens with a bonded length of 50 mm. The bond strength-slip performance was analysed to assess the impacts of the different surface roughness profiles. The results show that glass blasting creates a more robust bond behaviour than sandblasting.