Study Of High Performance Concrete And Its Property For Alkali Resistance

With the development of concrete materials and structure science, high performance concrete is widely applied in more projects, however, the problem of the durability of concrete structure becomes more serious. Alkali corrosion is one of the main reasons which influence the durability of concrete structure in the building of aluminum refinery. But the destruction of alkali corrosion to concrete materical actually reports very few, even sometimes it is wrongly considered that alkali is harmless to concrete.In order to research the new matericals of reinforcement concrete structural to resist corrosion in alkaline environments, this thesis analyzes the factors that influences the deterioration of concrete in the building of aluminum refinery, and also summarizes the nowadays measures to resist the corrosion of concrete. Finally, several kinds of material additives, which used widely and chemical admixtures are selected to be studied by a serial of systematic tests. In addition, the microstructures and mechanisms of these materials are tested and analyzed. Through researching the above several aspects, this thesis thoroughly analyzes the corrosion-proof of concrete material.In this thesis, freezing-thawing cycle resistance of fly-ash content concrete is researched by experiment, and the influence of different quantity fly ash to the anti-frozen performance of concrete is analyzed. The experimental results indicate: compared with 25% fly ash and 30% fly ash, 28% fly ash makes the anti-frozen performance of concrete best. Besides, the cement mortar is carried out to analyze the mechanical properties in different corrosion environments. It shows that the selected mineral additives such as fly ash, slag and chemical admixtures could also improve the performance of corrosion resistance of concrete exposed to the alkaline environments.The results indicate that double-combined mineral additives can improve interfacial transition zone and Ca (O H )2crystal pattern, increase C ? S ? Hgel quantity, make concrete denser and reinforce the durability of concrete.