Preparation And Properties Of High Strength Super-hydrophobic Concrete

Reinforced concrete structure with easy casting,impact resistance,wear resistance and other excellent features is the most widely used structural material and the largest amount of building materials in the world.However,in the special environment such as coastal engineering,saline soil,long-term use of deicing salt and cold zone,reinforced concrete structures can be significantly reduced in their structural durability due to corrosion or freezing and thawing,and most of the buildings occurs corrosion damage and the structure early invalid after running ten years,its seriously affecting the safe operation of the building.Super-hydrophobic surface with self-cleaning,anti-icing frost,corrosion and other excellent features and after through more than a decade of scientific research has shifted from theoretical experiments to multifunctional and high stability development.In view of the low durability of concrete structures in corrosive environment and cold environment,the paper applicate superhydrophobicity to improve the durability of concrete to prepare a kind of corrosion resistant concrete with high strength and superhydrophobic surface,and research the basic properties of concrete superhydrophobic surface,stability,anti-icing performance and other basic properties.Finally,test the concrete’s performance of anti-freeze-thaw damage and corrosion resistance.The paper based on the principle of "binary synergy",treat the concrete with low surface energy material fluorosilane and use the method of covering the copper mesh on the concrete surface to construct the micro-nanometer composite rough structure,and finally the superhydrophobic surface was prepared on the concrete surface successfully.The test results show that the contact angle of the super-hydrophobic surface of the concrete is 154.2°,the rolling angle is 6.8°,and the contact form of the water droplet on the concrete surface conforms to the Cassie-Baxter theoretical model.The results of the friction experiment show that the friction performance of concrete super-hydrophobic surface is better than commercial super-hydrophobic coating Never-wet,and the concrete super-hydrophobic surface have a strong capability of anti-friction damage.The results of anti-icing experiment in the environment of simulation of freezing rain show that the concrete superhydrophobic surface not only has a strong anti-icing performance but to remove the ice is easy.The experiment of the concrete water absorption shows that the rate of super-hydrophobic concrete’s water absorption is significantly lower than ordinary concrete.The water absorption in deionized water is only 41.6% of ordinary concrete,and in 3.5%NaCl solution is 19% of ordinary concrete.The freeze-thaw experiments of concrete show that the anti-freeze-thawing performance of super-hydrophobic concrete is improved greatly,The ordinary concrete was crushed and cracked after freeze-thaw cycle at 110 times,and the mass loss was 6.7%,while the super-hydrophobic concrete still no obvious damage when the freeze-thaw cycle at 210 times and the mass loss was only 0.26% after 190 times cycles.The analysis of polarization curves and electrochemical impedance spectroscopy of superhydrophobic concrete shows that the super-hydrophobic concrete has better corrosion resistance than ordinary concrete,and its corrosion resistance has certain durability.