Journal of the Korean Society of Mineral and Energy Resources Engineers ISSN:2288-0291(Print) 2288-2790(Online) 한국자원공학회지

The effects of specific surface area of blast furnace slag(BFS) and alkaline activator on the compressive strength of blast furnace slag cement were investigated. Sodium sulfate(Na2SO4) was used as alkaline activator. The addition amounts of alkaline activator, calculated in terms of Na2O, were 2.5 and 5.0wt.% to BFS weight, respectively. The flow and compressive strength of mortar were examined when the BFS power of which the specific surface area are 4,000, 6,000 and 8,000cm2/g were substituted for 30, 50, and 70wt.% of ordinary portland cement(OPC), respectively. As the results, the compressive strength of mortar increased with the increase of specific surface area of BFS and alkaline activator content when the mortar cured for 1 day and 3days. For the mortar cured for 7days, only the specific surface area of BFS affected the increase of compressive strength.