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中文摘要：
根据金属腐蚀极化理论推导了电化学极化控制和氧浓差极化控制两种条件下混凝土中钢筋腐蚀速率的理论模型．模型显示：电化学极化控制下，稳定腐蚀状态下能斯特扩散层以外孔隙液中Fe^2＋和OH^-的浓度对腐蚀速率的影响呈负指数关系，且影响随浓度降低而渐趋剧烈；温度对腐蚀速率有较大影响，约呈正指数关系，在自然温度范围内，温度每升高10K，腐蚀速率约升高1倍；应力对腐蚀速率的影响接近正线性关系，对应力较低的普通钢筋影响较小，但对应力较高的预应力钢筋影响可观；氧浓差极化控制下，腐蚀速率与氧气在整个混凝土保护层内的等效扩散系数呈正比，与混凝土保护层厚度及钢筋表面温度呈反比．
英文摘要：
Based on the corrosion polarization theories of metal, two theoretical models of the corrosion rate of steel bars embedded in concrete are derived, one is for the corrosion controlled by the electrochemical polarization and another is for the corrosion controlled by the concentration polarization of oxygen. The model for the electrochemical polarization indicates that （ 1 ） in a stable corrosion state, the corrosion rate is affected by the concentrations of Fe2＋ and OH- in the pore liquid beyond the Nemst diffusion layer in a negative exponential relation, and the effect becomes more visible with the decrease of the concentrations; （2） temperature greatly affects the corrosion rate in a approximately positive exponential relation; （3） in general, the corrosion rate approximately doubles when the temperature increases by 10K; and （4） stress affects the corrosion rate approximately in a positive linear relation, and the effect on ordinary steel bars under low stress is relatively small but proves remarkable on the prestressed rein- forcement under high stress. Moreover, the model in the concentration polarization condition indicates that the co- rrosion rate is proportional to the equivalent diffusion coefficient of oxygen in concrete cover but inversely propor- tional to the depth of concrete cover and to the temperature of steel bars.
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