Lightweight Strengthened Gypsum Stone for Restoration of Architectural Monuments

A way for further strengthening of modified lightened gypsum stone of white color for restoration of stucco in architectural monuments due to the use of metakaolin, superplasticizer, and hydrophobizator is proposed. The structure of this stone has been studied. It is proved that the introduction of metakaolin and a hydrophobic-plastisticizing additive in the gypsum mix compacts the gypsum matrix due to the change in element composition of the gypsum system with hollow glass micro-spheres, the increase in inter-planar distances and sizes of gypsum crystals. The authors consider that such changes increase the cross-sectional square and bearing capacity of gypsum crystals. It is established that the developed material has technical efficiency in terms of average density, specific strength, cohesion strength to the base, water resistance, and sorption humidity.

T.EH. HAEV, Engineer (This email address is being protected from spambots. You need JavaScript enabled to view it.),
E.V. TKACH, Doctor of Sciences (Engineering) (This email address is being protected from spambots. You need JavaScript enabled to view it.),
D.V. ORESHKIN, Doctor of Sciences (Engineering) (This email address is being protected from spambots. You need JavaScript enabled to view it.) 

1 Moscow state university of civil engineering (National Research University) (26, Yaroslavskoe Highway, Moscow, 129337, Russian Federation) 
2 Institute of Comprehensive Exploitation of Mineral Resources Russian Academy of Sciences (4, Kryukovskiy Tupik, Moscow, 111020, Russian Federation)

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