Photocatalytic Self-Cleaning Fine-Grained Concrete

The results of evaluating the ability of fine-grained concrete (FGC) modified with titanium dioxide (anatase) to self-cleaning, based on oxidation-reduction reaction of decomposition and removal of pollutants, are given. Different variants of introducing the modified anatase additive into the FGC composition and the finish surface are considered. According to the methodology of GOST R 57255–2016, the values of the contact wetting angle (CWA) of fine-grained concrete without an additive, with an additive into the FGC and the finishing layer, as well as on the surface of the finishing coating are defined. Three variation periods of the contact wetting angle are recorded. The first period is characterized by an intense decrease in the CWA. The most significant reduction occurs during the first 30 minutes of UV radiation exposure, then the process slows down (the second period), and stabilizes (the third period). The contact wetting angle is reduced to less than 5^о within 60 minutes of UV radiation exposure. This effect is achieved due to the modified anatase nanoparticles of less than 90 nm. The effectiveness of surface application of the modified anatase additive in comparison with its volume content is shown. The contact wetting angle decreases from 53.4^о to 5.1^о after 30 minutes of UV radiation exposure. At that, the CWA in the samples with TiO₂ as a part of the finishing layer changes to a lesser extent.

N.P. LUKUTTSOVA, Doctor of Sciences (Engineering) (This email address is being protected from spambots. You need JavaScript enabled to view it.),
R.A. EFREMOCHKIN, Master of engineering and technology, direction of “Construction” (This email address is being protected from spambots. You need JavaScript enabled to view it.),
O.I. BORSUK, Engineer (This email address is being protected from spambots. You need JavaScript enabled to view it.),
S.N. GOLOVIN, Bachelor (This email address is being protected from spambots. You need JavaScript enabled to view it.)

Bryansk State Engineering and Technology University (3, Stanke Dimitrova Street, Bryansk, 241037, Russian Federation)

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