Investigation Of Neutralization Of Concrete Under Loads By Accelerated Acid Rain Test

With the development of modern industry and the increase in energy consumption, the acid emissions have increased,and acid rain phenomenon is one of the top ten problems which are threat to the environment.Now China has become the third largest acid rain area in the world following Europe and North America.In the acid rain area,a large number of concrete structures exposed to the acid rain directly,and subjected to aid rain corrosion.That causes concrete neutralization,and results in the damage of concrete structure.Therefore,the corrosion of concrete under loads subjected to the attack of acid rain should be investigated,which is significant for the investigation of service life prediction and for the durability design and assessment of concrete structures.The acid rain attack tests are carried out based on the analysis of the neutralization mechanism of concrete under loads subjected to the attack of acid rain.The devices suitable for the tests were adopted,and the application and control of bending loads are determined.The paper emphatically studies the impacts of fly ash proportion(0%,15%, and 30%) and bending stress level(0,0.2,0.4,and 0.6) to concrete neutralization depths, and through the analysis to the results of the test,the bending stress coefficient of concrete neutralization is presented.A neutralization model for concrete under loads subjected to acid rain attack was proposed on the basis of the theory of diffusion and mass transfer,and the values of the model parameters were studied for the further.The model is reasonable as the results calculated by the model agree well with test results,and it lays a foundation for the prediction of service life of concrete structures under loads subjected to the attack.