Study on the performance and synergistic mechanism of cement mortar reinforced with combined superabsorbent polymers and basalt fibers admixture.

This study addresses the need for cement-based materials with high mechanical properties and reduced autogenous shrinkage by investigating the effectiveness of incorporating superabsorbent polymers (SAP) and basalt fibers (BF) to enhance the volumetric stability of cement mortar. The effects of individual and combined additions of SAP and BF on mortar were systematically evaluated through autogenous shrinkage tests, mechanical properties tests, and workability assessments, culminating in an optimized mixture. The synergy between SAP and BF was further examined by using Scanning Electron Microscopy (SEM) to observe changes in the surface microstructure of the cement matrix. The findings demonstrate that (1) the optimal proportions of SAP and BF are 0.25% each, leading to cement mortar with superior mechanical properties and improved volumetric stability; (2) SAP significantly reduces shrinkage strain by water absorption and subsequent water release, promoting hydration, while BF contributes to the stress distribution capacity of the matrix, particularly increasing tensile and flexural strength and reducing crack propagation; and (3) the synergistic interaction between SAP and BF enhances the interfacial microstructure and bonding, as well as reduces porosity following SAP-induced water release, thereby improving the mechanical properties and crack resistance of the cement mortar. [ABSTRACT FROM AUTHOR]