钢筋阻锈剂作用机理及效果研究

发布时间：2018-05-05 12:22

本文选题：钢筋锈蚀 + 内掺型阻锈剂　；参考：《内蒙古科技大学》2015年硕士论文

【摘要】：有机类复合型钢筋阻锈剂是目前最具应用前景的阻锈剂种类，但该类阻锈剂成分复杂、品牌多样，在相关研究中，不同人员对其阻锈效果的评价及阻锈机理的见解存在一定分歧。本文从有机类复合型钢筋阻锈剂对混凝土物理性能和钢筋锈蚀的影响出发，首先选用RCM试验、电镜扫描（SEM）以及XRD物相分析法综合评价了阻锈剂对混凝土密实度的影响，分析其添加对有害离子渗透所起的抑制作用，并探寻了阻锈剂对混凝土物理性能产生改变的原因；然后选用钢筋盐水浸渍试验、钢筋混凝土浸烘试验和钢筋表面形貌观测的方法评价了阻锈剂对钢筋的缓蚀作用，，分析了阻锈剂对钢筋表面钝化膜致密度的影响，总结了阻锈剂的阻锈机理；最后用电化学试验比较了不同添加情况下的阻锈剂对混凝土模拟液中碳钢锈蚀的阻锈效果，筛选出最合理的组合方式。通过试验，本文主要得到了如下结论：（1）有机类阻锈剂可使混凝土氯离子扩散系数降低，单独添加内掺型阻锈剂、外涂型阻锈剂以及同时添加内掺性和外涂型阻锈剂的试样所得氯离子扩散系数较空白组分别降低了16.8%、17.3%、23.5%。（2）XRD物相分析图表明，内掺型阻锈剂使混凝土内C3S和Ca(OH)2的衍射峰降低，促进了水泥的水化，含有减水剂成分。因此，在实际工程应用之前，需重视阻锈剂与其他外加剂的相容性分析，保证其对混凝土的物理性能无不良影响。（3）试验所选阻锈剂的阻锈机理为：①以促进混凝土水化或在混凝土微孔隙内形成沉淀的方式提高混凝土的密实性，减少有害离子的入侵；②阻锈分子吸附到钢筋表面形成致密的钝化膜，提高临界氯离子浓度。（4）钢筋阻锈剂在混凝土结构的阻锈效果明显，浸烘试验结果表明，单独添加内掺型阻锈剂、外涂型阻锈剂以及同时添加两种阻锈剂的试样所得钢筋锈蚀率较空白组分别降低了43.3%、51.3%、64.5%。（5）在混凝土模拟液试验中，通过改变添加方式可得到阻锈剂的最佳组合方式，浸渍试验、EIS测试以及Tafel极化曲线测试结果均表明，在测试开始便同时添加内掺型和外涂型阻锈剂的试样所得效果最优，阻锈效率分别为50.8%、54.1%、45.6%。
[Abstract]:The organic compound corrosion inhibitor for steel bar is the most promising corrosion inhibitor at present, but the composition of this kind of inhibitor is complex, the brand is diverse, in the related research, Different people have different opinions on the evaluation of rust inhibition effect and rust inhibition mechanism. In this paper, based on the effect of organic compound steel corrosion inhibitor on the physical properties of concrete and the corrosion of steel bar, RCM test, scanning electron microscope (SEM) and XRD phase analysis were used to evaluate the effect of rust inhibitor on the compactness of concrete. This paper analyzes on the inhibition effect of its addition on harmful ion penetration, and probes into the reasons for the change of the physical properties of concrete caused by rust inhibitor, and then selects the impregnation test of reinforced salt water to test the effect of corrosion inhibitor on the physical properties of concrete. The corrosion inhibition effect of corrosion inhibitor on steel bar was evaluated by immersion test of reinforced concrete and observation of steel bar surface morphology. The effect of corrosion inhibitor on the density of passivation film on steel bar surface was analyzed, and the corrosion inhibition mechanism of rust inhibitor was summarized. Finally, the corrosion inhibition effect of corrosion inhibitor on carbon steel in concrete simulated solution was compared by electrochemical experiments, and the most reasonable combination was selected. Through experiments, the main conclusions of this paper are as follows: 1) the diffusion coefficient of chloride ion in concrete can be reduced by organic rust inhibitor. The chloride diffusion coefficient of the sample with the addition of the inner-mixed rust inhibitor, the external rust inhibitor and the inner-mixed and outer-coated rust inhibitor can be reduced by 16.8and 17.3and 23.5respectively compared with the blank group. The diagram of phase analysis shows that the diffraction peaks of C _ 3s and Ca(OH)2 in concrete are decreased by adding rust inhibitor, which promotes the hydration of cement and contains water-reducing agent. Therefore, before the practical application, we should pay attention to the compatibility analysis of rust inhibitor and other admixtures to ensure that it has no adverse effect on the physical properties of concrete. 3) the corrosion inhibition mechanism of the corrosion inhibitor selected in the experiment is 1: 1 to improve the compactness of concrete and reduce the invasion of harmful ions by promoting the hydration of concrete or the formation of precipitation in the micropore of concrete. (2) the corrosion inhibitor molecules adsorbed on the surface of steel bar to form a dense passivation film, and the critical chlorine ion concentration was increased. (4) the corrosion resistance of steel bar in concrete structure is obvious. The results of soaking and drying test show that the corrosion rate of steel bar with the addition of inner-mixed rust inhibitor, external rust inhibitor and two kinds of corrosion inhibitor at the same time is decreased by 43.3% and 51.3%, respectively compared with the blank group, and the corrosion rate of steel bar is 64.5% lower than that of the blank group, and the results show that the corrosion rate of the steel bar is better than that of the control group. 5) the optimum combination of corrosion inhibitor can be obtained by changing the method of adding in the simulated liquid of concrete. The results of immersion test and Tafel polarization curve test show that, At the beginning of the test, the sample with both internal and external antirust agents has the best effect, and the corrosion inhibition efficiency is 50.8 and 54.1and 45.6, respectively.
【学位授予单位】：内蒙古科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU528.042.6

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