Wet-milling disposal of autoclaved aerated concrete demolition waste - A comparison with classical supplementary cementitious materials

The raw autoclaved aerated concrete waste (RA) is an important construction and demolition waste. The present work investigated the possibility of utilizing ultrafine autoclaved aerated concrete waste (WA) as a supplementary cementitious material (SCM) after wet-milling disposal. Results indicated that it is possible to realize the utilization of RA as a SCM by wet-milling treatment. The ultrafine WA blended mixture presented earlier hydration heat flow than the other alternatives. WA blended mixture showed almost the highest reactivity index (almost 100%) and compressive strength at each curing age, whereas coarse RA and SS blended systems presented the lowest values. WA blended mixture showed relatively low initial and secondary sorptivity coefficients. It was concluded that the high secondary sorptivity coefficients of FA and RA was due to the formation of connected voids by porous RA particles and partially reacted hollow FA spheres. (C) 2020 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.