| Popis: |
Huge amounts of Portland cement which is a main constituent material of concrete is manufactured and carbon dioxide (CO2) emitted by the manufacturing process of cement can cause global warming. Geopolymer (GP) contains no cement as a binder and several industrial by-products such as fly ash and blast furnace slag, so the spread of GP contributes to the reduction of global warming and the environmental load. GP has low CO2 emissions, high durability due to chemical attack and fire resistance, however, viscosity of GP is higher than that of cement concrete. Although chemical admixtures can be effective to the improvement of workability, most commercial products of them are for cement concrete. In this study, mortar flow and compressive strength of GP were experimentally evaluated in order to investigate effects of several chemical admixtures for cement concrete. Water glass and caustic soda solution were used as an alkaline-activating solution, and water glass causes high viscosity of GP mortar, so mortar flow test and compression test were conducted by using GP mortar with and without water glass. Test results indicate that the GP mortar without water glass had lower viscosity and lower compressive strength than that with water glass. The chemical admixture whose base component is naphthalenesulfonic acid was most effective to fluidity and compressive strength of GP mortar without water glass. |
