Mar 22, 2018
Final Report for Development of Durable "Green" Cementitious Materials Available
The CESTiCC project, Development of Durable “Green” Cementitious Materials Exposed to Freeze/Thaw and Deicing Chemicals in Cold Climate via Synergistic Use of Locally Available Recycled Materials and Multi-Scale Modifiers, has published its final report. In this study, a pure fly ash paste (PFAP) was developed in place of ordinary Portland cement paste (OPCP). This PFAP was prepared at room temperature and without direct alkali activation. The samples were prepared using only the as-received class C coal fly ash, water, and a very small amount of borax (Na2B4O7). On average, the PFAP featured 28-d compressive strength of about 36 MPa, and micro-nano hardness and elastic modulus 29% and 5%, higher than the OPCP, respectively. These mechanical and other properties of the PFAP make it a viable “green” construction binder suitable for a host of structural and non-structural applications. Advanced characterization of the raw material and PFAP pastes was employed to elucidate the hydration mechanisms of this “green” binder. The obtained knowledge sheds light on the role of class C CFA in the hydration process and may benefit the expanded use of various CFAs in cementitious materials.