| 초록 |
Three dimensional alumino-silicate cementitious material, termed 'geopolymer' has been widely studied to replace ordinary Portland cement(OPC). The requirements for construction materials such as high compressive strength and durability have been satisfied in geopolymer. Also, geopolymer is considered to be environmental-friendly because it emits dramatically less CO2 than OPC and can be synthesized from industrial wastes like coal combustion products(CCPs). In this study, the bottom ash as one of CCPs is employed as a source material after being ground and sieved because of its large and irregular size. Geopolymer specimens were prepared in a 5 cm cubic mold into which the ground bottom ash mixed with various concentrations of NaOH solution (from 8 M to 14 M) at proper liquid/solid ratios was poured. To accelerate the curing and drying process, a household microwave was additionally used after the specimens were set in a dry oven at 75 °C for a day. The highest compressive strength of more than 40 MPa was achieved with 14 M NaOH solution with thermal conductivity of lower than 0.52 W/m·K for all samples. |
