【作者】 殷国伟；

【导师】 于继寿；

【作者基本信息】 哈尔滨工业大学 ， 材料学， 2008， 硕士

【摘要】 混凝土中的钢筋锈蚀引起的混凝土结构过早破坏是导致混凝土耐久性不足的首要原因之一,给世界各国造成了巨大的经济损失。钢筋锈蚀已成为国内外学者们关注的热点问题。在混凝土中引入适量气体可以显著提高混凝土的耐久性,特别是在气候寒冷的北方地区,引气已成为提高混凝土抗冻性的最有效途径,而掺合料作为配制高性能混凝土必不可少的组分之一已被广泛应用,因此,研究掺合料和含气量对混凝土抗钢筋锈蚀性能的影响具有重要意义。本文以掺合料、含气量、水灰比、等因素作为变量制作了不同种类的含钢筋的混凝土试件。在三种不同加速锈蚀制度下,利用线性极化法测得的电化学参数来比较各种因素对混凝土抗钢筋锈蚀性能的影响,并用氯离子扩散系数和碳化深度分别来评价混凝土的抗渗性和抗碳化性能。试验结果表明,在热干湿交替加速锈蚀(盐水)和外加电流加速锈蚀条件下,混凝土抗钢筋锈蚀性能与抗氯离子渗透性之间存在着密切的关系,混凝土抗氯离子渗透性越好,其抗钢筋锈蚀性能也越强;28d和56d养护龄期时,在这两种加速锈蚀制度下,以30%混掺(矿渣:粉煤灰=1:1)方式制备的混凝土抗钢筋锈蚀性能最好。在淡水热干湿交替加速锈蚀条件下,混凝土抗钢筋锈蚀性能与抗碳化性能规律之间存在着密切的关系,即混凝土抗碳化性能越好,其抗钢筋锈蚀性能也就越优异;56d养护龄期时,在淡水热干湿交替加速锈蚀条件下,矿渣掺量为30%的混凝土抗钢筋锈蚀性能最好,而粉煤灰掺量为30%的抗钢筋锈蚀性能最差。热干湿交替加速锈蚀制度比通电法加速锈蚀能更好地模拟实际环境中混凝土内钢筋的锈蚀。含气量接近4%时,存在一最佳含气量值,使其抗渗性、抗碳化性能和抗钢筋锈蚀性能最好。更多还原

【Abstract】 Now in the world, the early structure failure of concrete caused by reinforcement corrosion is considerd as the principal factor to induce the deficiency of concrete durability and it has caused huge pecuniary loss to the world. The problem of reinforcement corrosion has been drawing extensive attention of academic circles. To induce proper volume of air by air entraining agents can obviously improve the durability of concrete, especially in the cold north of China, this has become the most effective step to raise frost resistence, while mineral admixtures has been widely used as one of the essential compositons to produce high performance concrete. Therefore, to research the influence of the mineral admixture and air content on the reinforcement corrosion resistence has important significance.In this paper, we prepare different kinds of concrete by the factors such as mineral admixtures, air content, W/C and so on. Under the three systems to accelerate corrosion process, we compare the impact of the various factors above on the corrosion resistance by the electrochemical parameters attained by the linear polarization method. Besides, we evaluate the impermeability and carbonization resistance by chloride ion diffusion coefficient and carbonization depth differently. The result indicates that, under the conditions of hot alternation of wetting and drying corrosion accerlating (saline) and external current flow corrosion accerlating, the corrosion resistance has close relationship with impermeability of concrete, that is to say, the better the impermeability is, the better the corrosion resistance is; under the two accerlating conditions, concrete prepared by the 30% mineral admixture (Slag: FA =1:1) enjoys the best corrosion resistance among them with 28d and 56d curing age, while under the hot alternation of wetting and drying corrosion accerlating (fresh water), the better carbonization resistance is, the better the corrosion resistance is, the concrete prepared by 30% of salg has the best corrosion resistance with 56d curing age. Compared with external current flow corrosion accerlating, the system of hot alternation of wetting and drying corrosion accerlating can better simulate the corrosion process under the pratical environment. When the air content induced into the concrete arrives at 4% or so, it will have the best impermeability、carbonization resistance and corrosion resistance.更多还原