침지된 해수 온도 및 결합재 혼합비에 따른 비소성 시멘트의 강도 특성

Abstract

This paper presents an investigation of the mechanical properties on non-sintered cement pastes immersed in sea waters at three differenttemperatures. The non-sintered cement pastes were synthesized using blended binder(Class F fly ash; FA and ground granulated blast furnace slag;GGBFS) and alkali activator(sodium hydroxide and sodium silicate). Binders were prepared by mixing the FA and GGBFS in different blend weightratios of 6:4, 7:3 and 8:2. The alkali activators were used 5wt% of blended binder, respectively. Calcium carbonate was used as an chemical additive. The compressive strength, bulk density and absorption of alkali-activated FA-GGBFS blends pastes were measured at 3 and 28 days after immersedin sea waters at three different temperatures(5°C, 15°C and 25°C). The XRD and SEM tests of the pastes were conducted at 28 days. Water-solublechloride(free chloride) and acid-soluble chloride(total chloride) contents in the pastes were also measured after 28 days immersion in sea water. Theexperimental results showed that increasing the content of FA in alkali-activated FA-GGBFS blends pastes immersed in sea water increases theabsorption, water-soluble chloride content and acid-soluble chloride content, and reduces the compressive strength and bulk density. And it was foundthat there was a variation of strength change for the alkali-activated FA-GGBFS blends pastes immersed in sea waters at three different temperaturesthat depends on the blending ratio of FA and GGBFS.