Experimental Study On The Impermeability And Anticorrosion Behavior Of Concrete

The corrosion of reinforcing bar is closely related to the permeability of concrete, it is decided by porosity and permeability of concrete by the root. Study the permeating mechanism and choose a suitable experimental method, research the relationship between permeability and corrosion from the theories and experiment, through the permeability to calculate corrosion will have the important theories and realistic meaning.In this thesis, the methods of water permeability test and NEL for measuring permeability of concrete were used. Through imitate the environment of dry/wet circulation and the chlorine ion erosion, measure the reinforcing bar in the different category concrete with the half battery electric potential method in the corrosion electric potential in the same erosion environment in the circulating period of two years. Compare the difference of anticorrosion behavior about the concrete of different category, the dissimilarity protection layer, different strength and the water ash ratio. Permeate the relation that sex experiments to experiment various index signs with the reinforcing bar rust eclipse. Build up the relationship of various experiment indexes between permeability and corrosion, analyze the function mechanism, and try to make use of permeability to evaluate its durability and then predict the service life of the concrete structure.The result of experiment indicate that decrease water/binder ratio, add with water-reducing agent, mineral admixture and the fiber can lower the coefficient of permeate and the chlorine ion spread coefficient, raise the impermeability and anticorrosion behavior of concrete. There is a certain related relation among the coefficient of permeate, the chlorine ion spread coefficient and half battery electric potential, and can predict the time when the reinforcing steel start to corrosion according to the chlorine diffusion coefficient.