Performance-based study on the rheological and hardened properties of blended cement mortars incorporating palygorskite clays and carbon nanotubes

摘要

In this performance-based study, the effect of palygorskite clays and carbon nanotubes (CNTs) on the rheological and hardened properties of a cement mortar and a blended mortar containing cement, fly ash and blast furnace slag were compared. Results showed that although the control cement mortar and control blended mortar exhibited similar rheological parameters, the additives had differing effects on each system. Palygorskite clays increased yield stress and static cohesion and decreased plastic viscosity in both systems but these effects were more marked in the cement mortar than in the blended. On the other hand, CNTs increased all measured rheological parameters in the cement mortar and decreased them in the blended. The rheological results highlighted the importance of considering the binder system when utilizing additives with exceptional surface properties like CNTs and palygorskite clays. In the hardened state, electrical resistivity, compressive strength, and tensile strength were evaluated. Results indicated that although the palygorskite clays are utilized primarily as a rheological modifier, they can also enhance mechanical properties. (C) 2018 Elsevier Ltd. All rights reserved.