The Effect of Fly Ash Qualify on the Properties of Concrete

The effect of high and low lime fly ash on the fluidity,compressive strength and long-term properties(carbonation,chloride ion diffusion coefficient,drying-wetting cycles)of concrete was studied.The test results showed that concrete with high and low lime fly ash have same slump of concrete,concrete with high lime fly ash has a higher compressive strength than that of low lime fly ash at the same curing period,the high and low lime fly ash have also effect on the carbonation depths,chloride ion diffusion coefficient and the damage under drying-wetting cycles of concrete,concrete with low lime fly ash has a higher carbonation depth than that of high lime fly ash,the high and low lime fly ash have not effect on chloride ion diffusion coefficient of concrete,the effect of high and low lime fly ash on deteriorate properties of concrete under drying-wetting cycles was studied,the parameter was the weight lost,the relative compressive strength and the relative dynamic of elasticity,the result indicates that concrete with low lime fly ash has a larger the relative compressive strength,relative dynamic of elasticity than concrete with high lime fly ash at the initial stage of drying-wetting cycle,the deteriorate degree of concrete with high lime fly ash is less than concrete with low lime fly ash after 30 days of dry-wet cycle.