State-of-the-art review on properties evolution and deterioration mechanism of concrete at cryogenic temperature

Cryogenic temperature has been widely recognized as one of the extreme environments for the application of concrete. Exposures to the cryogenic temperature may remarkably deteriorate the properties of concrete and thus shortening the service life of structures. This paper presents a comprehensive overview of cryogenic temperature effects on the mechanical properties, freeze-thaw failure, permeabilities and cracking of concrete. The influence of cryogenic temperature on the thermal parameters and deformation of concrete is discussed from the thermodynamic point of view. Based on the phase transformation process and structural characteristics of pore water in concrete at cryogenic temperature, the strengthening mechanism of mechanical properties at cryogenic temperature and the deterioration mechanism under cryogenic freeze-thaw cycles of concrete are analyzed and summarized. Generally, the mechanical properties of concrete at cryogenic temperature are improved whereas their degradation rate under cryogenic freeze-thaw cycles is much faster than that under the ordinary freeze-thaw condition. Meanwhile, compared with ambient temperature, the thermal properties of concrete vary greatly at cryogenic temperature. It is concluded that the phase transformation and migration of pore water in concrete have obvious influence on the variations observed in its properties. Hence, different models are proposed to understand the deterioration mechanism of concrete performance at cryogenic temperature. (C) 2020 Elsevier Ltd. All rights reserved.