Study On Durability Of Early - Age Concrete In Chloride Environment

As a large number of domestic and foreign concrete structures have appeared degradation of concrete durability ahead of time, the problem of concrete durability is more and more concerned by the specialists and scholars in academic and engineering fields. There are many factors leading to early failure of the concrete structure, of which the most important is the reinforcement corrosion caused by chloride ion erosion. The erosion is starting at once when concrete contacts with chlorine ion environment during pouring and curing process, not waiting for curing completed. So the research on durability of early age concrete is necessary.This paper takes the early age concrete as the research object, research on diffusion performance of chloride ion in concrete, the main research contents and achievements are listed as follows:1. The concrete specimen were designed about three different mix proportion, soaked in Na Cl solution of three different concentrations. Research the diffusion performance of chloride ion of early age concrete by measuring the chloride concentration laminated and chloride ion diffusion coefficient of concrete specimen. Experiments show that, resistance to chloride ion penetration of early age is very poor, penetration levels is senior.2. By SEM scanning electron microscope images, describe the change of cement hydration products’ form and content under chloride ion erosion. Combining microscopic structure and macroscopic permeability to give a more full and comprehensive theoretical foundation.3. Concrete structure in marine environment greatly accelerates the speed of chloride ion erosion because of wet and dry cycles. The experiments research on the effects of wet and dry cycle effects on chloride diffusion properties, simulating marine cyclic of wet and dry cycles,by measuring the chloride concentration laminated.