By Nitric Acid And Nitrate Corrosion Experiment On The Mechanical Properties Of Concrete

The reinforced concrete structure by nitrate corrosion due to long-term role, has resulted in deterioration of concrete, steel corrosion and the bond between the steel and concrete degradation, made durability of reinforced concrete structures lower in early damage. At present, owing to corrosion, it has been a disaster faced by civil engineering field caused by degradation of the reinforced concrete structure durability. So the durability of concrete structures has been a common phenomenon of the world widespread concerned by people and a heated issue focused by domestic and foreign scholars But so far it has still been lacking at home and abroad on the concrete nitrate corrosion work in this area Therefore, this paper mainly studied that physical and mechanical properties of concrete materials after corrosion based on summarizing the study of relevant corroded reinforced concrete properties at home and abroad .The mainly study contends are:1. It is studied that reinforced concrete structure on the durability of the research background, the significance and major research studies and research methods. The durability of reinforced concrete structure over the past 10 years of progress is summarized.2. It is the conclusion that reinforced and concrete corrosion mechanism made by various corrosion environment.3. The paper has a experiment on the durability study of ordinary concrete. In the process nitric acid and ammonium nitrate two chemical were used, have a test different levels of corrosion, through the concrete blocks of Accelerated corrosion experiments were taken by C15, C20, C30, C40, C50 concrete corroded by nitric acid in PH=2, PH=3, PH=4 and ammonium nitrate in 5 percent and 15% to get the compressive strength, weight and shape change made by their corrosion. The experimental results show that the strength of corroded concrete was promoted in the early increase, with the corrosion time increased concrete strength gradually declined. Based on the pilot study, it was proposed that the mechanism and regularity of concrete structure caused by the nitrate and nitrite corrosion to provides a basis for concrete maintenance and reinforcement4. Using X-ray diffraction, scanning electron microscopy (SEM), the concrete samples were observed and analyzed by nitric acid and ammonium nitrate corrosion from , the change of internal components was measured with soaking time changing, the relationship between micro structure change and macro-mechanical properties and the concrete corrosion mechanism caused by nitric acid and ammonium nitrate was also testified.