earticle

영어

This study deals with the non-portland cement mortar made with ground granulated blast-furnace slag, fly ash produced in combined heat power plant and paper sludge ash as binder. As a activator, gypsum (-CaSO4․1/2H2O) which is not strong alkali activator was used. As a result, mortar flow decreased as contents of paper sludge ash increased due to the water adsorption and the arching of paper sludge ash. The porosity of mortar was measured to evaluate the properties of crack and micro structure and the results showed that the porosity increased as water-mortar ratio and contents of paper sludge ash increased. Compressive strength of mortar used paper sludge ash was higher than that of others in early 3days but compressive strength was lower than that of others over 3 days. It was because CaO of paper sludge ash had the same hydration as type O expansion admixture and actual water-mortar ratio decreased due to the water adsorption of paper sludge ash. Also, the formation of Ca(OH)2, C-S-H (Ⅰ,Ⅱ ,Ⅲ), monosulphates and a large amount of ettringite as hydrates was observed.