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The article provides review of modern cement repair mortars for restoring the surface of reinforced concrete structures and analyzes their composition, properties, application technologies and environmental impact. The features of the composition of repair mortars and the role of mineral additives, hardening accelerators and nanomodifiers in the formation of the microstructure of cement mortar are shown. The possibility of using composite cements and alkali cements to obtain repair mortars with increased durability is demonstrated.

Dry mix mortars are widely used in construction projects for the implementation of construction works in new construction, reconstruction, and repair. The improvement of properties of dry mix mortars for the installation of floor screeds is relevant. The purpose of such mortars is to equalize the differences in the thickness of the floor surface, to create an intermediate layer characterized by the necessary strength, durability, and even surface with the possibility of decoration with various types of flooring.

One of the actual problems of the further sustainable development of construction industry is solution of energy and resource saving problems during production and reduction of harmful emissions. Building materials based on gypsum raw compared to cement materials of analogical purpose are characterized by low energy consumption, as well as better ecological indicators. However, gypsum materials without modifying additives have low strength and water resistance which limits their application to the area of internal processing of rooms with a relative humidity of up to 60 %.

The paper investigates the impact of natural zeolite and air-entraining agent on the properties of mortar mixtures and hardened mortars of different functional application. It is shown that the introduction of natural zeolite slightly increase water demand of mortar mixtures and reduced segregation. Optimization of mortar mixture with the addition of zeolite and air-entraining agent was carried out. Graphical interpretation of obtained results reveals that the highest strength parameters show mortar containing 8 wt.% of zeolite and 0,1 wt.% of air-entraining agent.