Study On Acid Rain Corrosion Model Of Concrete

The consumption of fossil fuel (coal and petroleum) is becoming more and more. So lots of sulfur oxide and nitrogen oxide is expelled during the combustion of these energy materials, which can be converted to vitriol and nitric acid. These acid materials fall down with rain or snow and that is so-called "acid rain", which is becoming an attractive environmental problem. In China, the southwest is the most serious part.First of all, the relationship between concrete strength, acidified depth and the solution density of SO₄^2- ,H⁺, marinating period and concrete initial strength before marinating is established with dimension analysis method.Secondly, the artificial acid rain solution used in the laboratory is confected with different density of SO₄^2- ,H⁺, The mass loss, flexural strength, compressive strength and acidified depth of the mortar, fine aggregate concrete, and normal concrete in different solutions are systematically studied through dry-wet cycles method.Thirdly, the mathematic model between mortar, fine aggregate concrete and normal concrete strength and the acidified depth has been gotten from the test data using nonlinear regression method under MATLAB condition. The model can comparatively predict the acid rain corrosion of concrete. Finally, two neural networks are established here with Back-Propagation network and Radial Basis Function network, which can be used to reflect the mortar flexural strength loss percentage and concrete compressive strength loss percentage.The mathematic model and the neural networks between strength after acidifying and acidified depth can reflect the corrosion condition of mortar and concrete, which have certain referential value for estimating the acidifying resistance durability of concrete in southwest China.