Investigation on the effect of various factors on the rate of corrosion of reinforcing bar in concrete and estimation of the life of RC buildings

含氯离子混凝土中钢筋腐蚀速率的长期室外暴露试验。试验条件为：氯化钠掺量（0~1.0%/砂）、水灰比（50~65%）、保护层厚度（15~ 40 mm）。结论如下。钢筋在长期室外暴露试验中的锈蚀量与暴露时间的平方根成正比。在氯化钠含量（0~0.3%/砂）范围内，钢筋锈蚀率随保护层厚度的增加而减小。提出了混凝土保护层厚度和水灰比对氯化钠含量腐蚀速率的估算公式。

The long term outdoor exposure test on the rate of corrosion of reinforcing bar in concrete which contains chloride ion. The factor of experiment are sodium chloride content(0～1.0%/sand), water-cement ratio(50～65%), and thickness of concrete cover(15～40mm). It is conclude as follows. The corrosion loss of reinforcing bar in long term outdoor exposure test increases in proportion to square root of exposure period. Rate of corrosion of reinforcing bar decrease with increasing thickness of concrete cover in sodium chloride content(0～0.3%/sand). The estimation equation of the rate of corrosion of sodium chloride content are proposed by thickness of concrete cover and water cement ratio.