Effect of Ultrafine Additives on the Morphology of Cement Hydration Products
Grigory Yakovlev,
Rostislav Drochytka,
Gintautas Skripkiūnas,
Larisa Urkhanova,
Irina Polyanskikh,
Igor Pudov,
Ekaterina Karpova,
Zarina Saidova,
Ali E. M. M. Elrefai
Affiliations
Grigory Yakovlev
Department of Construction Materials, Mechanization and Geotechnics, Kalashnikov Izhevsk State Technical University, Studencheskaya Str. 7, 426069 Izhevsk, Russia
Rostislav Drochytka
Department of Technology of Building Materials and Components, Faculty of Civil Engineering, Brno University of Technology, Veveří 331/95, 602 00 Brno, Czech Republic
Gintautas Skripkiūnas
Laboratory of Concrete Technologies, Faculty of Civil Engineering, Institute of Building Materials, Vilnius Gediminas Technical University, Saulėtekio al. 11, LT-10223 Vilnius, Lithuania
Larisa Urkhanova
Department of Building Materials, Roads and Woodworking, East Siberia State University of Technology and Management, 40V Klyuchevskaya St., 670013 Ulan-Ude, Russia
Irina Polyanskikh
Department of Construction Materials, Mechanization and Geotechnics, Kalashnikov Izhevsk State Technical University, Studencheskaya Str. 7, 426069 Izhevsk, Russia
Igor Pudov
Department of Construction Materials, Mechanization and Geotechnics, Kalashnikov Izhevsk State Technical University, Studencheskaya Str. 7, 426069 Izhevsk, Russia
Ekaterina Karpova
Laboratory of Concrete Technologies, Faculty of Civil Engineering, Institute of Building Materials, Vilnius Gediminas Technical University, Saulėtekio al. 11, LT-10223 Vilnius, Lithuania
Zarina Saidova
Department of Construction Materials, Mechanization and Geotechnics, Kalashnikov Izhevsk State Technical University, Studencheskaya Str. 7, 426069 Izhevsk, Russia
Ali E. M. M. Elrefai
Department of Construction Engineering, Faculty of Engineering, Egyptian Russian University, Cairo-Suez Road, Badr City 11829, Egypt
The present research is focused on the investigation of the influence of ultrafine additives on the structure formation of hardened cement paste and the establishment of the mechanisms of the morphological transformations, which determine the properties of hydrated products. In the course of the research, the modification of ordinary Portland cement was performed by the suspension of multi-walled carbon nanotubes (MWCNTs), carbon black (CB) paste, and silica fume (SF). Scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) microanalysis, X-ray diffraction (XRD) analysis, thermal analysis, and Fourier-transform infrared (FTIR) spectroscopy were used to study cement hydration products. The morphology of hardened cement paste depends on the chemical reactivity of additives, their geometry, and their genesis. The action mechanism of the inert carbon-based additives and pozzolanic silica fume were considered. The cement hydration products formed in the process of modification by both types of ultrafine additives are described. In the case of the modification of cement paste by inert MWCNTs and CB paste, the formation of cement hydration products on their surface without strong adhesion was observed, whereas in the case of the addition of SF separately and together with MWCNTs, the strong adhesion of additives and cement hydration products was noted.
