Acoustic Emission Signals of Pull-Off Test for Concrete Slab Strengthened with CFRP Using Various Surface Preparations

This study investigates the acoustic emission signals of concrete slab strengthened with carbon fibre reinforced polymer (CFRP) under pull-off test. Three types of surface preparations were prepared namely without surface preparation, normal surface preparation and boring surface preparation. The slabs were then tested under pull-off test in conjunction with acoustic emission technique. The pull-off strength, acoustic signal strength, amplitude, duration and rise time were analysed and discussed. It was found that the boring surface preparation produced the highest pull-off strength compared to other surface preparations, indicating good bonding between the CFRP and the concrete interface. This study is useful in identifying the bonding between CFRP and concrete using acoustic emission technique.