Experimental Study On Concrete Durability-Resistance To Chloride Ion Permeability And To Freezing And Thawing

The durability of reinforced concrete structure is now one of the questions that should to be solved on civil engineering sector. Based on the actual construction situation, the article makes a key research on two aspects about reinforced concrete structure durability:resistance to Chloride Penetration and the concrete Freezing-thawing damage.Through the research on the index of resistance Chloride Penetration and the processing and analysis of testing data in construction, the article proposed the method that using initial current to calculate electric flux and proved the feasibility of this method in construction; Analyzed the correlation of electric flux and penetration. Proposed synthetic method to test Electric Flux and Permeability experiment, which can be good for indicators consistency and practical comparative application.Using orthogonal design method, researching on the resistance of Freeze-thaw with different admixture and cement, proposing instructive views for actual construction:the frost resistance of the ordinary concrete added fly ash and slag can reach more than F300 with a appropriate dosage of mixture and suitable gas content; However, if the mixture replaced by equivalent, the impact of fly ash and slag to the Freeze-thaw resistance is negative, Particularly, the fly ash has greater impact than slag. Thus, the replacement rate of fly ash should be reduced or the cement should be replaced by excess; the frost resistance of ordinary concrete has no direct relationship with the strength of concrete; the frost resistance of the ordinary concrete added fly ash and slag would change with different cement which can not be replaced on different concrete mixing test.The achievement of the experimental study of the article may provide a reference for the reinforced concrete engineering project.