Functional Bi<sub>2</sub>O<sub>3</sub>/Gd<sub>2</sub>O<sub>3</sub> Silica-Coated Structures for Improvement of Early Age and Radiation Shielding Performance of Cement Pastes
Krzysztof Cendrowski,
Karol Federowicz,
Mateusz Techman,
Mehdi Chougan,
Ahmed M. El-Khayatt,
H. A. Saudi,
Tomasz Kędzierski,
Ewa Mijowska,
Jarosław Strzałkowski,
Daniel Sibera,
Mohamed Abd Elrahman,
Pawel Sikora
Affiliations
Krzysztof Cendrowski
Faculty of Civil and Environmental Engineering, West Pomeranian University of Technology in Szczecin, 70-311 Szczecin, Poland
Karol Federowicz
Faculty of Civil and Environmental Engineering, West Pomeranian University of Technology in Szczecin, 70-311 Szczecin, Poland
Mateusz Techman
Faculty of Civil and Environmental Engineering, West Pomeranian University of Technology in Szczecin, 70-311 Szczecin, Poland
Mehdi Chougan
Department of Civil and Environmental Engineering, Brunel University London, Uxbridge UB8 3PH, UK
Ahmed M. El-Khayatt
Department of Physics, College of Science, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh 11564, Saudi Arabia
H. A. Saudi
Department of Physics, Faculty of Science, Al-Azhar University, Women Branch, Nasr City 11754, Egypt
Tomasz Kędzierski
Department of Nanomaterials Physicochemistry, Faculty of Chemical Technology and Engineering, West Pomeranian University of Technology in Szczecin, 70-310 Szczecin, Poland
Ewa Mijowska
Department of Nanomaterials Physicochemistry, Faculty of Chemical Technology and Engineering, West Pomeranian University of Technology in Szczecin, 70-310 Szczecin, Poland
Jarosław Strzałkowski
Faculty of Civil and Environmental Engineering, West Pomeranian University of Technology in Szczecin, 70-311 Szczecin, Poland
Daniel Sibera
Faculty of Civil and Environmental Engineering, West Pomeranian University of Technology in Szczecin, 70-311 Szczecin, Poland
Mohamed Abd Elrahman
Structural Engineering Department, Mansoura University, Mansoura City 35516, Egypt
Pawel Sikora
Faculty of Civil and Environmental Engineering, West Pomeranian University of Technology in Szczecin, 70-311 Szczecin, Poland
This study presents a new approach towards the production of sol-gel silica-coated Bi2O3/Gd2O3 cement additives towards the improvement of early mechanical performance and radiation attenuation. Two types of silica coatings, which varied in synthesis method and morphology, were used to coat Bi2O3/Gd2O3 structures and evaluated as a cement filler in Portland cement pastes. Isothermal calorimetry studies and early strength evaluations confirmed that both proposed coating types can overcome retarded cement hydration process, attributed to Bi2O3 presence, resulting in improved one day compressive strength by 300% and 251% (depending on coating method) when compared to paste containing pristine Bi2O3 and Gd2O3 particles. Moreover, depending on the type of chosen coating type, various rheological performances of cement pastes can be achieved. Thanks to the proposed combination of materials, both gamma-rays and slow neutron attenuation in cement pastes can be simultaneously improved. The introduction of silica coating resulted in an increment of the gamma-ray and neutron shielding thanks to the increased probability of radiation interaction. Along with the positive early age effects of the synthesized structures, the 28 day mechanical performance of cement pastes was not suppressed, and was found to be comparable to that of the control specimen. As an outcome, silica-coated structures can be successfully used in radiation-shielding cement-based composites, e.g. with demanding early age performances.
