Feasibility of using construction residual soils to develop cold-pressing recycling coarse aggregates

The cold-pressing technique, which incorporates the principles of cement chemistry and composite material was employed to produce the recycling coarse aggregates using B2-3, B3, B4, and B6 categories construction residual soils with extremely low utilization rate and poor properties so as to raise the utilization rate and value of the above-mentioned construction residual soils. The results show that the specific gravity of recycling coarse aggregate is about 1. 80 in the oven-dry(OD) state and 2.05 in the saturated-surface-dry(SSD) state; the absorption capacity is approximately 15.5% (by mass): the bulk density (i. e. unit weight) is 1103 to 1 216 kg/m ³: the air void is about 35.3% (by volume); the particle cylindrical crushing strength ranges from 17.06 to 23.33 MPa; other characteristics meets requirement set forth in ASTM C33. For this reason, the developed recycling cold-pressing coarse aggregates can not only meet the specifications for green building materials, but can also be used to reduce the energy consumption and CO ₂ emission resulted from producing the sintering recycling aggregates.