Analyzing Engineering Properties Depending on Combination of Fly Ash and Blast Furnace Slag for High Strength Range Ternary Cement Mortar

고강도영역 3성분계 시멘트 모르타르에서 FA와 BS의 혼합비율 변화에 따른 공학적 특성 분석

The aim of the research is to deduce the optimal combination of fly ash and blast furnace slag for high strength range ternary cement mortar by evaluating the engineering properties of cement mortar depending on various combination of fly ash and blast furnace slag. According to the experiment, as the replacing ratios of supplementary materials were increased, the flow was increased, and for the air content, with increasing content of fly ash, generally, air content was decreased due to the unburnt carbon in fly ash. However, when the fly ash was included 65 %, the air content was increased by entrapped air. The unit mass of the mortar was decreased for increasing portion of fly ash because of relatively lower density of fly ash than blast furnace slag. The setting time was delayed with increased either entire supplementary materials and content of fly ash. Regarding the compressive strength, for each early and later ages, 25 and 65 % of supplementary materials replacements produced high compressive strength, respectively. The autogenous shrinkage was increased with increased content of blast furnace slag. In summary, regarding the compressive strength development, for early age, 25 % of supplementary materials consisted with 60 to 40 for fly ash to blast furnace slag while for later age, 65 % of supplementary materials consisted with 20 to 80 for fly ash to blast furnace slag.