Materials Science. Non-Equilibrium Phase Transformations.
Vol. 12 (2026), Issue 1, pg(s) 39-43

Influence of microstructural modification of cement-based composites on transport processes and long-term reliability

  • 1 State University of Novi Pazar, Department of Technical and Technological Sciences, Faculty of Civil Engineering, Novi Pazar, Serbia
  • 2 University of Pristina, Faculty of Technical Sciences, Architecture, Kosovska Mitrovica

Abstract

The long-term durability of cement-based composites is strongly influenced by their microstructural characteristics and resistance to the transport of water and aggressive ionic species. This study presents a parametric numerical investigation of the influence of binder modification on transport-related properties and predicted chloride penetration in cement-based composites. Four representative compositions were analysed: a reference Portland cement composite (REF), a mixture containing 10% silica fume (SF10), a mixture containing 15% metakaolin (MK15), and a hybrid mixture incorporating 5% silica fume and 10% metakaolin (HYB). The comparative assessment included accessible porosity, initial sorptivity, chloride migration coefficient and a proposed dimensionless Transport Resistance Index (TRI). Long-term chloride penetration was additionally evaluated using a simplified one-dimensional Fickian transport model for exposure periods of up to 50 years. Within the adopted parametric scenario, the HYB composition exhibited the most favourable overall performance, with reductions of approximately 28.3% in accessible porosity, 51.0% in initial sorptivity and 69.0% in chloride migration coefficient compared with the reference composite. The predicted comparative chloride penetration depth after 50 years decreased from approximately 134.5 mm for REF to 74.8 mm for HYB. The time required to reach a comparative penetration depth of 50 mm increased from approximately 6.9 years for REF to 22.3 years for HYB. Strong descriptive correlations were observed between accessible porosity, sorptivity and chloride transport. The results indicate that optimised binder modification may significantly improve resistance to transport processes and delay chloride penetration. However, the presented results should be interpreted as a comparative parametric analysis requiring subsequent experimental validation before application to quantitative structural service-life prediction.

Keywords

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