| 초록 |
Geopolymer is a green alternative to Ordinary Portland cement (OPC) because of much lesser CO2 emission during its production compared to OPC. However, the compressive strength of the geopolymer with a coal bottom ash which now has much attention for its reclamation is not good for the purpose of construction materials because of its irregular and large particle size with impurity components. To solve this problem, we have prepared specimen as follows: (1) mix bottom ash with low amount of alkali activator (NaOH) to reduce the effect of impurity dissolution, and then mold it in 5 cm cubic size, (2) heat the demolded specimen in 75 °C drying oven for 12, 24 and 36 hours, and (3) finally, microwave under 700 W power for several minutes. The compressive strength increases proportionally to oven curing times whereas there is an optimal irradiation period of microwave for each drying time. The highest compressive strength of 41.5 MPa is obtained in specimen cured in oven for 36 hours and microwaved for 3 minutes. Within only two days, much higher compressive strength is achieved than OPC. |
