纳米ZnO抗菌高性能混凝土性能试验研究

发布时间：2018-05-14 16:41

本文选题：高性能混凝土 + 正交试验　；参考：《宁夏大学》2016年硕士论文

【摘要】：本文针对混凝土的耐久性以及提高抗菌问题,借助粉煤灰、矿粉和聚丙烯纤维等复掺的微粉级配效应和纳米ZnO的抗菌性能,采用正交试验、对比试验的方法,以宏观和微观试验作为研究手段,对复掺混合材混凝土耐久性和绿色抗菌等进行了较为系统的研究,主要研究结果概括如下：(1)通过正交试验,优选出了混凝土配合比的最优组为A2B1C2D3E1,即水胶比为0.34,粉煤灰掺量为10%,矿粉掺量为20%,砂率为40%,聚丙烯纤维掺量为0.55kg/m3。三种混合材复合能显著提高混凝土的工作性能。(2)抗碳化性能试验：研究结果表面,混凝土的抗碳化能力随着龄期的增大而增大；随着粉煤灰、矿粉和聚丙烯纤维的掺入,优化了混凝土内部的孔结构,降低了孔隙率,使得抗碳化性能良好,但随着后期粉煤灰与水泥水化产物中Ca(OH)2反应,碳化减弱。由于纳米ZnO的掺加与水化产物反应生成了ZnCO3和 CaZn2(OH)6·2H2O,附着于水化物表面,抗碳化能力减弱。(3)抗硫酸盐侵蚀试验：混凝土的抗硫酸盐侵蚀能力随着龄期的增大而增大；随着粉煤灰、矿粉和聚丙烯纤维的掺入,起到填充作用,优化了混凝土内部的孔结构,降低了孔隙率,密实度提高,抑制SO42-的渗入扩散,同时对混凝土的膨胀性能有一定的缓冲和削弱作用,减缓腐蚀速度。由于纳米ZnO的掺加,大量附着在水化物表面使得混凝土孔隙增大,加剧了SO42-的渗入与扩散,造成硫酸盐腐蚀进一步加剧,抗硫酸盐侵蚀能力分别降低6.74%和5.35%。(4)抗菌试验：通过对掺加纳米ZnO的高性能混凝土进行大肠杆菌和金黄色葡萄球菌的定性试验,证明对两种菌种都具有抗菌抑菌能力。通过对掺加纳米ZnO的高性能混凝土进行对大肠杆菌和金黄色葡萄球菌的定量试验,结果证明两组抗茵混凝土对大肠杆菌的抗菌率都达到100%,对金黄色葡萄球菌的抗菌率分别为54.61%和99.12%。
[Abstract]:In this paper, aiming at the durability of concrete and the improvement of antimicrobial properties, the orthogonal test and contrast test method are used to improve the durability of concrete and improve the antimicrobial properties of nano-ZnO by means of the gradation effect of micro-powder mixed with fly ash, mineral powder and polypropylene fiber and so on. The durability and green antibacterial properties of mixed concrete were studied systematically by macroscopical and microcosmic tests. The main results were summarized as follows: (1) orthogonal test was carried out. The optimum mix ratio of concrete is A 2B 1C 2D 3E 1, that is, the ratio of water to binder is 0.34, the content of fly ash is 10, the amount of mineral powder is 20, the sand ratio is 40 and the content of polypropylene fiber is 0.55 kg / m ~ 3. The results show that the carbonation resistance of concrete increases with the increase of age, and with the addition of fly ash, mineral powder and polypropylene fiber. The pore structure of concrete was optimized, the porosity was reduced, and the carbonation resistance was good, but the carbonation decreased with the Ca(OH)2 reaction between fly ash and cement hydration product in the later stage. Because of the reaction of nano-ZnO with hydration products, ZnCO3 and CaZn2(OH)6 _ 2H _ 2O are formed, which are attached to the surface of hydrated compounds, and the carbonation resistance of concrete is weakened. 3) the sulfate corrosion resistance of concrete increases with the increase of age, and increases with the increase of fly ash. The addition of mineral powder and polypropylene fiber plays a filling role, optimizes the pore structure inside the concrete, reduces the porosity, increases the density, inhibits the infiltration and diffusion of so _ 42-, and has a certain buffering and weakening effect on the expansion performance of concrete. Slow down the corrosion rate. Due to the addition of nanometer ZnO, a large amount of adhesion to the surface of hydrates increases the pore size of concrete, which intensifies the infiltration and diffusion of so _ 4 ~ (2-) and further exacerbates the sulphate corrosion. The ability to resist sulfate erosion was reduced by 6.74% and 5.35% respectively. The antibacterial test was carried out on the high performance concrete mixed with nanometer ZnO. The qualitative test of Escherichia coli and Staphylococcus aureus showed that the two kinds of bacteria had antibacterial and bacteriostatic ability. The quantitative test of Escherichia coli and Staphylococcus aureus was carried out on high performance concrete mixed with nanometer ZnO. The results showed that the antimicrobial rate of the two groups was 100% against Escherichia coli and 54.61% against Staphylococcus aureus and 99.12% against Staphylococcus aureus respectively.
【学位授予单位】：宁夏大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TU528;TB383.1

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