Fracture behaviour characterisation of FRP-reinforced concrete based on digital image correlation and acoustic emission technology

Abstract

In order to identify the dynamic fracture characteristics of fibre-reinforced polymer (FRP)-reinforced concrete, three-point bending fracture tests of FRP-reinforced concrete with five different strain loading rates (10−1/s, 10−2/s, 10−3/s, 10−4/s and 10−5/s) are carried out. The fracture behaviour of FRP-reinforced concrete is analysed using digital image correlation (DIC) and acoustic emission (AE) techniques. Crack propagation in FRP-reinforced concrete beams during the fracture process is observed and a quantitative relationship is established between the AE parameters and the load level before the ultimate load is reached. Test results on the variation of the AE parameters can characterise the internal damage behaviour of the FRP-reinforced concrete beams and monitor the distribution characteristics of any cracks. The crack propagation trajectory of the FRP-reinforced concrete beams can be observed using the DIC technique and quantitative analysis of the crack opening displacement (COD) can be achieved.