超疏水涂层对混凝土抗冻性及防冰性影响研究

发布时间：2018-01-30 00:19

本文关键词： 超疏水涂层混凝土抗冻性防冰性　出处：《哈尔滨工业大学》2015年硕士论文　论文类型：学位论文

【摘要】：混凝土是当今使用最广泛的建筑工程材料之一,由于其多孔特性易吸收水分,在寒冷气候下导致抗冻耐久性不足发生冻融破坏或者表面结冰影响交通安全。针对目前常用的抗冻性或除冰手段存在不同程度的缺陷,本文拟引入超疏水涂层,以提高其抗冻性和防冰性。本文通过低成本工艺制备超疏水溶液,并采用一步喷涂法对混凝土表面进行超疏水处理,然后研究超疏水涂层对其抗冻性及防结冰性的影响。首先,通过水解缩合反应得到纳米-微米级二氧化硅颗粒,然后利用氟硅烷氟化法获得超疏水溶液。本文比较不同处理方法的疏水效果,测试了超疏水涂层混凝土的接触角、吸水率以及浸渍深度等基本性能。通过研究超疏水涂层对混凝土抗冻性的影响,结果表明由于超疏水涂层不能进入其孔内且疏水材料本身耐久性不足,仅靠超疏水涂层不能有效提高抗冻性;另一方面,引气与超疏水涂层处理相结合能够改善内部结构同时增强表面疏水性,从而有效提高抗冻性。最后,本文研究了超疏水涂层对混凝土表面结冰性及疏冰性两方面的影响,结果显示,具有倾斜角时,水滴可以轻易滚落,超疏水涂层提高了结冰势垒,涂层延缓了结冰时间,从而减少了结冰量;另外,超疏水涂层有效阻止了混凝土表面孔内结冰现象,有效降低了冰与混凝土表面的粘结强度,从而具有良好的疏冰性。此外,根据混凝土表面的粗糙及多孔结构特点,本文给出了描述混凝土表面粘接强度的经验公式。
[Abstract]:Concrete is one of the most widely used building engineering materials. Because of its porous characteristics, it is easy to absorb water. Freezing and thawing damage or icing on the surface may affect traffic safety in cold climates. In view of the defects of common freezing resistance or deicing methods at present, superhydrophobic coatings are introduced in this paper. In order to improve its frost resistance and ice resistance, the superhydrophobic treatment of concrete surface was carried out by one-step spraying method. Then the effect of superhydrophobic coating on freezing resistance and ice resistance was studied. First, nano-micron silica particles were obtained by hydrolysis condensation reaction. The hydrophobic effect of different treatment methods was compared and the contact angle of superhydrophobic coated concrete was measured. By studying the effect of superhydrophobic coating on the frost resistance of concrete, the results show that the superhydrophobic coating can not enter its pore and the durability of hydrophobic material itself is insufficient. The superhydrophobic coating alone can not effectively improve the frost resistance. On the other hand, the combination of air entrainment and superhydrophobic coating treatment can improve the internal structure and enhance the surface hydrophobicity, thus effectively improving the frost resistance. The effect of superhydrophobic coating on the ice-forming and ice-repellency of concrete surface is studied in this paper. The results show that the droplets can roll down easily and the superhydrophobic coating increases the ice-forming barrier. The coating delayed the freezing time, thus reducing the amount of icing. In addition, superhydrophobic coating effectively prevents the formation of ice in the pore of concrete surface, effectively reduces the bond strength between ice and concrete surface, thus has a good ice thinning property. According to the characteristics of rough and porous concrete surface, an empirical formula is given to describe the bonding strength of concrete surface.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU528

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