LAUSR

Abstract This study aimed to investigate the influence of low temperature ranging from −20 °C to 0 °C on the compressive strength and pore structure of a certain pile foundation concrete in the permafrost regions in China. This study analyzed concrete microstructure by low-temperature SEM. To quantify the influence of freezing amount, the relationship model of the compressive strength of concrete in a low-temperature environment was established based on the theory of accumulative curve of liquid saturation. Compressive strength increased with decreasing temperature. This finding was due to the gradual decrease in the pore radius of the water–ice phase transformation of concrete, and the amount of ice increased. This condition forms a complete and compact ice body and concrete bond, which gradually reduces concrete porosity. The calculated value of concrete compressive strength model established under pore icing is consistent with the experimental value.