Abstract: In order to improve the practical application of alkali-activated fly ash concrete in engineering, the variation law of compressive strength of alkali activated fly ash concrete at different ages（7、28、56 d） was studied based on different dosages of alkali activator （quicklime powder）（5%、8%、10%） and fly ash（10%、15%、25%）. The results showed that under the condition of constant content of quicklime powder, the 7-day compressive strength of alkali-activated fly ash concrete gradually decreased with the increase of fly ash content;at the ages of 28 and 56 days, the compressive strength of alkali-activated fly ash reached its maximum when the fly ash content was 15%. Under the condition of constant fly ash content, when the content of quicklime powder increased from 5% to 8%, the compressive strength of alkali-activated fly ash concrete at all ages increased;when the content of quicklime powder increased from 8% to 10%, the compressive strength of alkali activated fly ash concrete at all ages decreased.

Key words: material dosages, age, alkali activation, quicklime powder, fly ash, concrete, compressive strength