摘要
依据电化学原理 ,考虑了混凝土碳化规律以及钢筋锈蚀后半径变化对预测钢筋锈蚀率的影响 ,同时把氧化在混凝土中的扩散系数视为随时间变化的变量 ,提出了一个新的预测模型 ,并通过分析这一模型产生误差的原因 ,提出了用模型因子对预测公式进行修正 .同时 ,理论分析表明 :采用一般的混凝土碳化表达式与采用简化的混凝土碳化表达式相比 ,钢筋锈蚀率预测值会有显著差别 ;而考虑钢筋半径随锈蚀率的增加而减小以及氧气在混凝土中扩散系数随时间变化更符合实际情况 ;另外 ,在同一混凝土构件中 ,箍筋锈蚀程度要比纵筋更为严重 。
Based on the theory of corrosion electrochemistry, a new predeterminate model of steel bar corrosion ratio in concrete under common air condition is established, which considered the effect of Concrete Carbonation Model (CCH) and the variation of steel bars radius. Theoretical analysis shows both that consideration is necessary, meanwhile, the stirrup would be corroded more seriously than the longitudinal steel bar in the same member, so that it is necessary to pay important attention to the problem of shear failure. The relationship between the steel corrosion ratio and parameters in the predeterminate model is also discussed in the paper, and some useful results are obtained.
基金
浙江大学曹光彪高科技发展基金重点资助项目 !(2 2 32 961 51 0 2 3)
关键词
混凝土
碳化
钢筋锈蚀率
预测模型
耐久性
失效
concrete carbonation
steel corrosion ratio
predeterminate model
durability
