Evaluating Corrosion Conditions of Steel Bars in Concrete

• Main Author: 王家儀
• Other Authors: 林喻峰
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/91045757456191305903

碩士 === 建國科技大學 === 土木與防災研究所 === 100 === The main purpose of this research is to evaluate corrosion conditions of steel bars in concrete by non-destructive testing, using an electrochemical method able to detect the corrosion potential of steel bars in concrete and concrete current impedance. According to ASTM C876 description, when the corrosion potential measurement values of the steel bar below -350 mV, corrosion may be more than a 90 percent chance. If the concrete current impedance below 10 kΩ-cm, the Steel bar there is the possibility of corrosion. In accordance with the different corrosion factors, the factors of the test planning changes are as follows: concrete containing different concentration of chloride ions, and the steel bar to connect the current to accelerate the corrosion reaction. In addition, plan the use of spraying the solution of chloride ions, the simulation of reinforced concrete structures by sea tidal erosion, the observation of reinforced concrete corrosion process, as the future use of electrochemical detection reference. According to the experimental observations, the concrete containing chloride ions is very easy to cause internal corrosion of the steel bar. In addition, the specimens were placed in a large area of water vapor, water will penetrate through the pores will lead to concrete impedance and corrosion potential decreased, resulting in early damage to reinforced concrete. Current impedance of the concrete can be used as the basis for assessment of concrete internal humidity and moisture content, with the increase in curing time of concrete resistance was correspondingly increased.