Study on Hydration and Mechanical Property of Portland Cement-Blended Recycled Plaster Materials

In this work, Portland cement- (OPC-) blended recycled plaster materials (R-CP) were prepared to find out their hydration and mechanical properties. It was found that the hydration of R-CP was accelerated by the rapid rehydrated ettringite (AFt), and the strength of R-CP was decreased by the reduced hemihydrate content and low strength of rehydrated AFt and CaCO3. On the contrary, consistent with the previous studies, the strength of OPC-blended plaster of Paris materials (POCP) was improved by the formation of AFt, Ca(OH)(2), and CaCO3 that filled pores in the pastes. Therefore, a different strength development could be seen in POCP and R-CP. In principle, these findings will lay a solid ground work for the utilization of recycled plaster.