Performance of NSM CFRP strengthened concrete using modified cement-based adhesive at elevated temperature

•Efficiency of the cement-based adhesive in high temperature compared to epoxy.•A comparable temperature of failure between 235 and 255°C.•Cement adhesive showed better performance of about 1.8 times to that of epoxy at elevated temperature. Strengthening of concrete structures using fibre-reinforced polymer (FRP) composites has been utilized successfully for retrofitting a large number of structures around the world. This is required in case of increasing the applied loads, design and construction errors, updating of existing codes, or reduction of strength due to the deterioration of structure over time. The strengthening technique with FRP composites has been applied successfully using epoxy adhesives for concrete structures. The research showed the rapid degradation of properties of epoxy matrix with increasing temperature and this temperature is limited only below its glass transition temperature of the epoxy (Tg). Therefore, replacing the epoxy adhesive with cementitious bonding agent can enhance the performance of the strengthened structure at high temperatures. This test program was conducted to assess the efficiency of bonding strength between near-surface mounted (NSM) carbon fibre reinforced polymer (CFRP) textile and concrete using modified cement-based adhesive at elevated temperature. The conclusion showed a comparable efficiency of the modified-cement adhesive as a promising bonding material in FRP strengthening at high temperature climates.