Wood-Cement Compositions with Structures Modified at Macro-, Micro-, and Nano-Levels

The possibility of improvement of physical-technical characteristics of wood-cement compositions (WCC) by optimizing the structure at micro-, macro-, and nano-levels due to the regulation of sizes of wood filler particles and the use of additives of micro- and nano-dispersed silica is considered. It is established that the optimization of the grain composition of an organic filler makes it possible to obtain wood-cement compositions with compressive strength of 3.24 MPa that exceeds the compressive strength of samples produced without optimizing the grain composition of the filler by 45–49%. It is proved that the maximum increase of the compressive strength up to 9.4 MPa takes place when 30% of micro-silica is introduced into the composition. This is caused by two factors: the presence of silicon dioxide of amorphous modification in the additive of micro-silica which reacts with calcium hydroxide with formation of low-basic calcium hydro-silicates; compacting action of micro-particles filling the space between cement particles in the paste and products of hydration in the cement stone. The use of additives is due to their ability to interact with Portlandite and other products of cement hydration forming hardly soluble mixed salts which seal the pores. The structures with more dense packing are created and, as a result, WCCs with high physical-technical characteristics are produced.

E.Yu. GORNOSTAEVA, Candidate of Sciences (Engineering) (This email address is being protected from spambots. You need JavaScript enabled to view it.)
I.A. LASMAN, Candidate of Sciences (Engineering) (This email address is being protected from spambots. You need JavaScript enabled to view it.)
E.A. FEDORENKO, Candidate of Sciences (Engineering) (This email address is being protected from spambots. You need JavaScript enabled to view it.)
E.V. KAMOZA, Master student (This email address is being protected from spambots. You need JavaScript enabled to view it.)

Bryansk State Engineering-Technological University (3, Stanke Dimitrova Avenue, Bryansk, 241037, Russian Federation)

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