Effect of Silica Fume with Hydrated Lime on Compressive Strength and Carbonation Rate of C۲۵ Concrete

In this study ۱۱ different combinations of micro fly ash and calcium oxide were replaced instead of cement. Fly ash with ۵%, ۱۰%, ۱۵% and ۲۰% of cement and calcium oxide with ۵%, ۱۰%, ۱۵% and ۲۰% of cement and then a combination with fixed ۱۵% fly ash and ۵%, ۱۰% and ۱۵% of calcium oxide are replaced instead of cement. Then ۱۰۸ sample of cubic concrete have been prepared and samples at the ages of ۷, ۲۸ and ۵۶ days were applied compression strength and ultra sound tests and results were recorded and compared. According to the results, the samples had the best results at ۵۶ days. The reason for the good results at ۵۶ days was the entry of pozzolan into the system and its reaction with calcium hydroxide resulting from the hydration reaction.

کلیدواژه ها:

Fly ash ، Calcium oxide ، Compression strength test ، Ultra sound test ، Pozzolan