본 연구에서는 저탄소 친환경 콘크리트의 일반적인 원재료로 널리 알려져 있는 플라이애시, 고로슬래그미분말을 혼합하여 알칼리 활성화 결합재를 제작한 후, 양생 조건에 따른 내구성을 파악하고자, 탈형한 시험체를 15 및 25°C의 해수에 양생 시켜 재령 91일까지의 내구 특성을 살펴보았다. 플라이애시와 고로슬래그미분말의 혼합비에 대해서 일부 혼합에 대해서는 재령 28일에 비해 재령 91일에서 흡수율 증가 및 강도 감소를 나타났지만, 그 이외에는 양생 조건에 관계없이 재령에 따라 흡수율 감소 및 강도 증가를 보여주었다.
This paper presents an investigation of the mechanical properties on alkali-activated binders immersed in sea water. The alkali-activated binders 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 ratios 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 and absorptiion were measured at the age of 3, 7 and 28 days, and the XRD and SEM tests were performed at the age of 28 days.
This study investigate mechanical properties of alkali-activated slag fiber-composites according to water to binder ratio. A series of experiments were carried out to find the mechanical properties including compressive strength, uniaxial tensile tests. The result of tests exhibited strain hardening behavior and high ductility under direct uniaxial tensile load test.
This study investigates the fundamental properties of the water-binder (W/B) ratio and fine aggregate-binder (F/B) ratio in the alkali-activated slag cement (AASC) mortar. The W/B ratios are 0.35, 0.40, 0.45, and 0.50, respectively. And then the F/B ratios varied between 1.00 and 3.00 at a constant increment of 0.25. The alkali activator was an 2M and 4M NaOH. The measured mechanical properties were compared, flow, compressive strength, absorption, ultra sonic velocity, and dry shrinkage. The flow, compressive strength, absorption, ultra sonic velocity and dry shrinkage decreased with increases W/B ratio. The compressive strength decreases with increase F/B ratio at same W/B ratio. Also, at certain value of F/B ratio significant increase in strength is observed. And S2 (river sand 2) had lower physical properties than S1 (river sand 1) due to the fineness modulus. The results of experiments indicated that the mechanical properties of AASC depended on the W/B ratio and F/B ratio. The optimum range for W/B ratios and F/B ratios of AASC is suggested that the F/B ratios by 1.75~2.50 at each W/B ratios. Moreover, the W/(B+F) ratios between 0.13 and 0.14 had a beneficial effect on the design of AASC mortar.