Preparation and properties of coordinated solid waste-based synergistic activated cementitious materials

Efficient and high-value utilization of solid waste materials have significant economic, social and environmental benefits. The objective of this paper is to introduce a new kind of coordinated solid waste-based synergistic activated cementitious materials (Slag-fly ash solid-based cementitious materials, S-F-SCM) used to the binder of concrete with RAP (Reclaimed Asphalt pavement, RAP) aggregate. The optimal formula of S-F-SCM, mechanical properties, shrinkage and anti-carbonation performance of S-F-SCM were investigated by a series of laboratory tests. Results show that the S-F-SCM have good mechanical, shrinkage and anti-carbonation performance. The 28d compressive strength can reach up to 85.02 MPa. The slag proportion has a significant impact on the shrinkage characteristics of S-F-SCM. The lower the slag content, the better shrinkage properties. The research also found that the CO2 adsorption and desorption curves of S-F-SCM is differed from the theoretical results. The main hydration products of S-F-SCM are C-A-S-H, C-S-H, C-(A)-S-H and N-A-S-H gel phases.