The influence of freeze-thaw methods on the frost resistance of concrete paving flags

The object of research is the concrete of single layer and double layer paving flags made by vibropressing technology. The purpose of this work is to study the effect of freezing and thawing methods on the frost resistance of concrete paving flags. Method. In this work, some samples of paving flags were subjected to freezing and thawing from all sides and the other part through one side (other surfaces of the specimen were thermally insulated). The frost resistance was evaluated by the measurement of mass scaled from the top surface of samples after 20 freeze–thaw cycles. Results. The obtained results allow us to conclude that the method of freezing and thawing exposure has a significant effect on the frost resistance of concrete. The freezing and thawing through one side of samples led to the appearance of temperature gradients along the height of the paving flags, which model more severe operating conditions than freezing and thawing from all sides of samples.