Effect of corrosion‐induced crack and corroded rebar shape on bond behavior

Abstract

This paper aims to investigate the individual effect of corrosion‐induced crack, corroded rebar shape, and rust around rebar on the bond properties of reinforced concrete (RC) members. First, test specimens were corroded by accelerated electric corrosion method with varying corrosion degree ranging from 0 to 25%. Test specimens were divided into different groups. For the normal corrosion group, bond test was conducted directly after the corrosion test to investigate the combined effects including corrosion‐induced crack, corroded rebar shape, and rust on bond deterioration. In another group, after corroded rebar was taken out from test specimen, rust was removed before casted into new concrete to evaluate single effect of corroded rebar shape. Similarly, corroded rebar with rust was casted into new concrete to evaluate the effect of the formation of rust on bond degradation. Experimental results quantitatively illustrate the influential factors including corrosion degree, corrosion crack width and geometry of corroded rebar. As the important finding, corrosion crack in concrete is concluded to be a more dominant factor than the corroded rebar shape and rust accumulation in bond deterioration mechanism. Moreover, rust accumulation contributes to the improvement of bond deterioration induced by corroded rebar shape.

Time‐dependent model and life prediction for reinforcement corrosion in magnesium oxychloride cement concrete

“…Based on References 44–52, our studies established the time‐dependent model for reinforcement corrosion in MOCC and predict the MOCC structure service life. The time‐dependent model and life prediction for reinforcement corrosion in MOCC are the highlights of this paper.…”

“…There are many basic time-dependent models for reinforcement corrosion in concrete before the concrete cracks, for example, Vu and Stewart, Yalcyn and González model, andso on 22,[44][45][46][47][48][49][50][51][52] ; however, only three representative models were selected in this paper.…”

Effect of fly ash and corrosion on bond behavior in reinforced concrete

“…28 Namely, during the whole accelerated corrosion procedure, the corrosion loss of OPC was greater than that of FAC. It can be speculated that the theoretical degrees of corrosion calculated by Equation (1) and the experimental corrosion degrees of steel bars were always different. Therefore, after the pull-out test procedure, it is also necessary to determinate the actual degree of corrosion.…”

“…However, the corrosion of steel bars remarkably reduces the bond performance of RC structures. 1 The products generated from steel corrosion will form the corrosioninduced expansion force around reinforcement, leading to cracking and spalling of concrete cover, 2,3 which provides a more convenient channel for harmful substance (such as chloride ions, CO 2 molecules, moisture and oxygen) to get into concrete and attack the steel bars. This adverse effect can accelerate the corrosion propagation rate, 4,5 and then destroy the bond behavior.…”

“…Bond performance is a crucial index for evaluating the cooperative work of reinforced concrete (RC) structures. However, the corrosion of steel bars remarkably reduces the bond performance of RC structures 1 . The products generated from steel corrosion will form the corrosion‐induced expansion force around reinforcement, leading to cracking and spalling of concrete cover, 2,3 which provides a more convenient channel for harmful substance (such as chloride ions, CO 2 molecules, moisture and oxygen) to get into concrete and attack the steel bars.…”