Cracks width-corrosion rate correlation on the durability of reinforced concrete in a very high aggressiveness tropical marine environment

Abstract

This study aims to evaluate the correlation between crack width and apparent corrosion rate in reinforced concrete specimens exposed to a tropical marine environment of very high aggressiveness. Specimens from DURACON project (prismatic 15x15x60 cm), with 0.65 and 0.45 w/c ratios were monitored in this investigation for more than a 6-year period. Six of them have six reinforcing steel bars (rebars) placed at three different depths (two each at 15, #y20 and 30 mm) for electrochemical tests, and six specimens without reinforcement were used for concrete destructive testing. These specimens were exposed for more than 6 years at the station La Voz, Venezuela.Each day, the meteorochemical parameters (relative humidity, temperature, precipitation, wind speed and Cl-) were monitored. Also, once a month, the electrochemical parameters (corrosion potential and corrosion rate) were measured. This paper presents the results obtained with the0.65 w/c ratioconcrete specimens, which were the only ones that presentedcorrosion-induced surface cracks. Results obtained shown excellent linear correlation between mean maximum crack width and rebar cross section loss, depending also on the rebar's concrete cover.