考虑混凝土碳化影响的钢筋腐蚀速率研究

Study on the Corrosion Rate of Steel Bars Considering the Influence of Concrete Carbonation

摘要: 为探究钢筋混凝土(RC)结构中钢筋锈蚀速率的影响因素，建立了RC结构中考虑碳化影响的钢筋锈蚀速率模型，进而以常益长铁路常德站站房RC结构为研究对象，探究了混凝土碳化指数、混凝土保护层厚度、钢筋直径、暴露时间等参数对钢筋锈蚀速率的影响。结果表明：(1) 钢筋锈蚀速率随碳化指数增大而显著增大，混凝土碳化规律的对钢筋锈蚀速率影响较大。(2) 钢筋锈蚀速率随混凝土保护层厚度的减小而显著增大，当混凝土保护层厚度不能满足设计要求时，RC结构将更快锈蚀。(3) 钢筋锈蚀速率随钢筋直径增大而减小，碳化指数越大，钢筋直径对钢筋锈蚀速率的影响越大。(4) 钢筋锈蚀速率随暴露时间增大而显著增大，并大致呈线性关系。

Abstract: In order to explore the influencing factors of steel corrosion rate in reinforced concrete (RC) structures, a model of steel corrosion rate considering the influence of carbonization in RC structures was established. Then, taking the RC structure of Changde Station of Changyi-Changde Railway as the research object, the effects of concrete carbonization index, concrete cover thickness, steel bar diameter and exposure time on steel corrosion rate were investigated. The results show that: (1) The corrosion rate of steel bars increases significantly with the increase of carbonization index, and the carbonization law of concrete has a great influence on the corrosion rate of steel bars. (2) When the concrete cover thickness cannot meet the design requirements, the RC structure will be corroded faster. (3) The corrosion rate of steel bar decreases with the increase of steel bar diameter. The larger the carbonization index, the greater the influence of steel bar diameter on the corrosion rate of steel bars. (4) The corrosion rate of steel bar increases significantly with the increase of exposure time, and it is roughly linear.