Forecasting crack resistance of short- and long-term loaded coatings

The paper presents crack resistance problem of polymer and polymer-cement coatings used for surface protection of concrete structures. In a result of analysis of operating conditions of the arrangement elements: coating – concrete and loads assisting them in different situations but also anticipated results of their effects, evaluation criteria of crack resistance of protective polymer coatings and polymer-cement ones subject to the activity of short-term and long-term load were work out. On the basis of six coating materials there was made a research verification of crack resistance criteria and effects of mechanical short-term and long-term to crack resistance were defined. Tests carried out showed correctness of worked out criteria for crack resistance and proved their usage in designing protective coatings for concrete structures.