Global warming is one of the most important problems in the world. It is necessary for many countries to reduce emission of carbon dioxide for sustainable society. It can reduce the emission from manufacturing cement to use fly ash as alternative binder to cement generally. This study shows influence of curing temperature changes to performance of fly ash as a binder. Curing temperature variations are 4 conditions in this experiment; Condition-A is 20℃ or 30℃. Condition-B is 10℃ in early-age and 20℃ or 30℃ after curing at 10℃. Condition-C is that curing temperature is a graded rise from 10℃ to 30℃. Condition-D is curing in water outside. It investigates compressive strength of mortar,
k-value and amount of calcium hydroxide at each condition. It also evaluates strength and
k-value with maturity(temperature-time factor), which is cumulative temperature. Fly ash fraction in this experiment is 15% in mass of binder. Maturity can evaluate strength of mortar even if datum temperature is - 10℃ as usual. On the other hand,
k-value can not be evaluated with maturity in this case. However, if datum temperature is suitable for the reaction of fly ash, for example, it is from 13 to 19℃ in this experiment,
k-value also can be evaluated by maturity. Datum temperature is 17℃ in this experiment and it can change depending on quality of fly ash used. It is found that, even if it is cured in low temperature and fly ash cannot react well in early age, fly ash can react and contribute to strength of mortar as a cementitious material in higher temperature environment. Therefore fly ash could be used more generally depending on curing condition and fly ash fraction.
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