Recycling of Hardened Cementitious Material by Pressure and Control of Volumetric Change

抄録

This study proposes a novel method for recycling concrete waste by compaction. The advantages of the proposed method include its high production speed and complete recycling; all of the concrete waste was used without segregation of gravel or other components. First, hardened cement paste (HCP) was examined, crushed, milled, and compacted. These formed compacts showed high strength. Compacts of hardened concrete (HC) were prepared after crushing and milling; however, their strength was low. The processes of adding HCP or sludge cakes and performing carbonation treatment were investigated to increase the HC compact strength, and all treatments were found to be effective. Another advantage of this compaction method is that the control of volumetric changes due to moisture loss or absorption can be achieved by adequately drying the powder before compaction.