Influence of assumed absorption capacity of superabsorbent polymers on the microstructure and performance of cement mortars

A correctly selected absorption capacity of SAP in cement paste is quite important for the microstructure and performance of internally cured cement-based materials. In present work, various water absorption capacity values were assumed to investigate the impacts of water exchange behavior of SAP on the performance and microstructure of cement mortars. The over-entrained water content due to the rapid desorption as well as the real effective water-to-cement ratio during the mixing was quantified and was proved to be the key factor for the notably decreased mechanical strength and anti-transport property (electrical resistivity), as well as the clearly increased fluidity and capillary porosity. However, no negative influence on the self-desiccation and shrinkage mitigation was observed. (C) 2019 Elsevier Ltd. All rights reserved.