Glass fibre reinforced polymer bars in concrete compression members

Abstract

The use of Glass Fibre-Reinforced Polymer (GFRP) composite materials as reinforcement for concrete structures to overcome corrosion problems has been growing. Past Canadian applications are dominated by bridge decks and car parks where de-icing salts are used. Other applications include coastal structures and structures aiming for improved durability. Our research aimed to examine the practicality of using GFRP bars as reinforcement in concrete compression members. Twenty-four concrete columns reinforced with either steel or GFRP were loaded in compression until failure, with ultimate compressive strengths and horizontal displacements of the bars recorded. The results indicate that the use of GFRP bars as reinforcement in concrete compression members is technically viable, with GFRP reinforced columns yielding almost the same capacity as those reinforced with equal areas of steel. Incorporation of extra GFRP stirrups was found to improve the capacity in bending of the longitudinal GFRP reinforcement. Cost comparisons have also been completed to ensure the use of GFRP reinforcement is economically viable. The research concluded that reinforcing concrete columns with GFRP bars is an attractive option when life span and/or durability are of high priority. The research was followed by the first design and construction of reinforced concrete compression members utilising GFRP in Australia. This was done at the Dundas Point Boardwalk on the Swan River in Applecross, Western Australia, completed in 2014. Ongoing research will initiate in 2015 at UWA to investigate GFRP subject to combined bending and axial stressing.