Carbonation curing of concrete is an emerging technology that sequesters CO₂ in cement matrix while improving the material properties. Given the fact that concrete is the world’s most used man-made material, its CO₂ utilization capacity is high. Since majority of concrete products are reinforced with steel, CO₂ utilization potential will be tremendously enhanced if all reinforced concrete can be treated by carbonation curing. However, the carbonation corrosion becomes a concern. This paper is to show if carbonation curing of reinforced concrete could be performed under ambient pressure, the concrete structure would be more corrosion resistant. It was found that reinforced concrete product so produced could attain 11 % CO₂ uptake based on cement content. The rebar corrosion behavior in the carbonation-cured concrete was examined using a natural ponding test and an accelerated impressed current (IC) test independently. Results suggested that the ambient pressure carbonation improved concrete resistance to the chloride-induced corrosion due to the densified carbonate-rich surface layer. In the natural ponding test, a lower macrocell current and a lower total corrosion value were observed in the carbonation-cured concrete during the 33-month wet-dry cyclic exposure of a chloride solution. The chloride contents at the rebar location in carbonation-cued concrete were also decreased. In addition, carbonation curing was found to delay the corrosion-initiation stage. The IC-accelerated corrosion test verified that carbonation curing improved the concrete resistance to chloride penetration by lowering the current and inhibiting the corrosion-propagation, leading to an enhanced structural integrity and an extended service life after corrosion initiation.

混凝土碳化养护是一项新兴技术，可将 CO ₂隔离在水泥基体中，同时改善材料性能。鉴于混凝土是世界上使用最多的人造材料，其 CO ₂利用率很高。由于大多数混凝土制品都是用钢筋加固的，如果所有钢筋混凝土都可以进行碳化养护，CO _{2 的}利用潜力将大大提高。然而，碳化腐蚀成为一个问题。本文旨在说明如果钢筋混凝土在常压下进行碳化养护，混凝土结构将更耐腐蚀。结果表明，这样生产的钢筋混凝土产品可以达到 11 % CO ₂基于水泥含量的吸收。分别使用自然积水试验和加速外加电流 (IC) 试验来检查碳化固化混凝土中的钢筋腐蚀行为。结果表明，由于致密的富含碳酸盐的表面层，环境压力碳化提高了混凝土对氯化物引起的腐蚀的抵抗力。在自然积水试验中，在氯化物溶液 33 个月的干湿循环暴露期间，在碳化固化混凝土中观察到较低的宏电池电流和较低的总腐蚀值。碳化混凝土中钢筋位置的氯化物含量也降低了。此外，发现碳化固化延迟了腐蚀引发阶段。