Cracking of concrete cover in reinforced concrete under various corrosion distributions

초록

It has been generally assumed that corrosion occurs uniformly around a rebar. However, corrosion may start from the outer portion of a steel bar because chlorides are generally penetrated into concrete in one direction under usual sea environments. Thus, the steel bar may not corrode uniformly around the rebar. The objective of the present study is therefore to investigate the cracking behavior of concrete cover under various corrosion distributions. Four different types of corrosion distributions were considered to study cracking behavior of concrete cover. The cover depth-to-rebar diameter ratios were also varied from 0.5 to 2. The present study indicates that the pressures to cause cracking of concrete cover under non-uniform corrosion conditions are much smaller than that under uniform corrosion. This means that cracking occurs much earlier under highly non-uniform corrosion condition and thus service life may be reduced considerably if one considers non-uniform corrosion realistically. The effects of rebar diameter and cover depth-to-rebar diameter ratio were also investigated.