Directions for ensuring the quality of gypsum-lime binders during restoration

Purpose: to consider issues related to the standard definition of the strength characteristics of an air binder and a cement binder. To show a technological solution to the problem of regulating the strength of an air binder stone by stabilizing care during setting and hardening. Methods: during the research, GOST 23789- 2018 “Gypsum binders. Test methods”. Results: a distinctive feature of restoration plaster solutions is that structure formation and strength gain occur only in an air-dry environment. As a result, the availability of approved and applied standards for the manufacture and use of restoration plaster solutions does not fully guarantee the creation of a reliable and safe environment for the life of an architectural heritage monument. It has been established that the mechanical characteristics (compressive and bending strength limits), as well as elastic parameters should be the same or lower in historical and restoration solutions in order to avoid changes in stress distribution. Practical significance: developed taking into account the comprehensive care of hardening stone, gypsum-lime binders can have a wide range of applications. They can be used as mortars for the preservation of architectural heritage and in the reconstruction of modern buildings, self-supporting partitions, fire protection elements or drywall (in places where a higher mechanical load is expected).