Abstract

Superabsorbent polymer (SAP) has been commonly used to mitigate the shrinkage of alkali-activated slag (AAS) pastes through internal curing. However, the effectiveness of internal curing might be affected by the microstructure of the pastes. Therefore, the effects of incorporating limestone powder (LP) on the microstructure and shrinkage of AAS pastes containing SAP are studied. The results reveal that incorporating LP mitigates the autogenous shrinkage of the pastes with SAP. This is because the incorporation of LP reduces the fraction of mesopores in the pastes containing SAP, while adding SAP maintains the internal relative humidity and increases the size of minimum pores that can drive autogenous shrinkage. In contrast, adding LP tends to enhance the driving force of autogenous shrinkage in the pastes without SAP due to the conversion of mesopores to gel pores. Furthermore, incorporating LP simultaneously enhances the reaction and generates more macropores in the pastes, causing a negligible influence on their mechanical properties and an increase of drying shrinkage. Overall, incorporating LP promotes the internal curing effectiveness in decreasing the autogenous shrinkage of the pastes.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.