Mechanism of concrete frost destruction

Theoretical substantiation and experimental confirmation of a low-modulus inclusions (particles) role, including closed air entrainment pores while concrete frost destruction and increase of its frost resistance is carried out. It is shown that the low-modulus inclusions evenly distributed in the concrete structure are a brake for the cracks formed during pore water freezing growth, thereby increasing the frost resistance of concrete. It has been theoretically proved that the proposed hypotheses describe the possible pressure formation and development processes during intrapore water freezing and are not a mechanism of the frost destruction. The essence of the frost destruction mechanism is the process of the cracks formation, accumulation and growth after volumetric stress field formation in the concrete structure, which average value exceeds the structure tensile strength. T.S. Powers hypothesis currently recognized as the main hypothesis cannot explain many of the theoretical and practical facts available accompanying the concrete frost destruction. The essence of the concrete frost destruction mechanism is revealed and described based on the modern science positions - fracture mechanics.