Christiansen, M.S.; Øster, K. (2014)
Anvendelse af bioaske i beton. Bearbejdelighed og hærdning
BEng thesis (In Dansih)
In this thesis co-combustion ash from coal and wood from HOFOR Amagerværket is used in the experimental work. The water solubility of the ash is 14% with sulphats salts being a major part of the soluble fraction. The initial setting time is prolonged by partly replacing cement or sand with the ash. If the ash should be used in concrete, there are a number of factors to consider. If 5% of cement is replaced with ash the compressive strength of the mortar is not affected by the ash replacing cement. If more than 10 % cement is substituted, the concrete strength is reduced th a high extent. There is no indication that the soluble salts in the ash affect the compressive strength significantly; the strength depends rather on the amount of solids. However, the salt has a huge impact on the consistency of the fresh mortar.
Download report