Investigation of Bond Strength and Flexural Behaviour of Frp-Strengthened Reinforced Concrete Beams Using Cement-Based Adhesives

• Published in: Australian journal of structural engineering Vol. 11; no. 2; pp. 129 - 139
• Main Authors: Hashemi, S, Al-Mahaidi, R
• Format: Journal Article
• Language: English
• Published: Routledge 01.01.2010
• Subjects: Adhesives; Concrete; Concrete beams; Fibre-reinforced Polymer (FRP); Fire testing; Joints (Engineering); Strength of materials; Testing
• ISSN: 1328-7982; 2204-2261
• DOI: 10.1080/13287982.2010.11465061

Retrofitting of structures has become a major issue worldwide due to increases in the applied loads, human error in initial construction, legal requirement to comply with updated versions of existing codes, or the loss of strength due to deterioration over time. In this regard, fibre-reinforced polymer (FRP) retrofitting systems are enjoying a great deal of popularity as a result of the unique properties of FRPs. Retrofitting with epoxy-bonded FRP composites is suitable for environments where the temperature is well below the glass transition temperature (T g ) of the epoxy adhesive. T g is normally in the range of55-60 °C (fib, 2001; Saafi, 2002). It would be very beneficial if it is replaced with cementitious (mineral) based bonding agents in order to produce fire-resistant strengthening systems. Pilot testing conducted by the authors has shown that excellent bonding properties can be achieved using the cement-based adhesives (Hashemi & Al-Mahaidi, 2009). Test results were applied for the next stage of the project presented in the current paper. Tests include the investigation of bond strength of FRP fabrics to the concrete substrate by single-lap shear test and flexural behaviour of FRP-strengthened reinforced concrete beams using cement-based adhesives. The bond-slip response has been developed for the strengthening system. It is concluded that using cement-based bonding materials is a promising technique in FRP applications for structures located in hot regions or in danger of fire.