Experimental and numerical investigation on flexural bond strength behavior of corroded NBS RC beam

Abstract

Corrosion of reinforcing steel is the most detrimental effect endangering the structural performance. Present investigation has been taken up to study the detrimental effect of corrosion on bond behavior. Experimental and numerical investigation has been carried out for four different levels of corrosion—2.5, 5, 7.5 and 10 %. Loss in mass of reinforcement bar has been taken as the basis to fix corrosion levels. Accelerated corrosion technique has been adopted to control corrosion rate by regulating current over predetermined durations. NBS beams have been investigated for performance. Concrete grade M30 and steel Fe-415 have been used. From the experimental investigation, it has been observed that bond strength degradation of 2.6 % at slip initiation and 2.1 % at end of slip have been observed for every percentage increases in corrosion level. Numerical investigation with concrete is modeled as solid 65 element and reinforcement modeled as Link 8 elements. ANSYS has yielded 3 and 2.4 % bond strength degradation values at initiation and end of slip per percentage increase in corrosion levels.