건설재료시공학연구실

Building material & construction lab.

In this study, effect of types and replacement ratio of alkali activator on compressive strength of ground granulated blast furnace slag mortar have been reviewed. Types of alkali activator are NaOH, Ca(OH)2, Na2SO4,and KOH. Replacement ratio of alkali activator is 7.5, 10, 12.5, 15% respectively. As results, under high temperature curing condition, the 1 day compressive strength development with NaOH and KOH was higher than Ca(OH)2, Na2SO4. Regardless of types of alkali activator, compressive strength increased with increasing pH. It can be accounted for that impermeable film on the surface of slag which is generated when slag meets water has been destroyed by alkali activator, and this promotes hydration reaction. Also, 1 day age compressive strength of specimen with high temperature curing was higher than that of specimen with standard curing. 28 days age compressive strength of specimen with high temperature curing was less than or equal to that of specimen with standard curing.