Experimental study on the bond-slip behavior between the shape steel and PVA fiber concrete

This study aims to investigate the bond-slip behaviour between shaped steel and polyvinyl alcohol (PVA) fibre-reinforced concrete, a critical aspect affecting the structural performance of steel-concrete composite structures. The experiment on 14 specimens, considering various parameters such as concrete strength, cover thickness, anchorage length, PVA fibre volume, and the presence of shear studs were conducted. A novel experimental method was devised to analyse the bond-slip characteristics between shaped steel and PVA fibre concrete. All specimens exhibited failure due to the bond between shaped steel and concrete. The load-slip curve exhibited four distinct stages: the initial stage, slip stage, descending stage, and horizontal residual stage. Notably, the addition of PVA fibre significantly enhanced the load-bearing capacity, with optimal performance observed at a fibre volume of 8 kg/m^3, surpassing conventional concrete bond strength. Moreover, increasing PVA concrete strength, anchorage length, and the use of shear studs were found to augment the bond strength. To further understand this bond-slip behaviour, a constitutive model correlating bond strength with characteristic slip values was developed, and it aligns well with experimental results, validating its accuracy and applicability.