Abstract: In order to study the variation of mechanical properties of concrete at different curing ages and high temperatures, the compressive strength and splitting tensile strength of concrete at different curing ages were tested by setting different temperatures and continuing curing time. The test results show that the compressive strength and splitting tensile strength of concrete at each age basically decrease with the increase of temperature, but when the temperature is not higher than 100 ℃ and the age is not more than 14 days, the strength increases slightly. Under the condition that concrete experiences the same temperature, the earlier the age at high temperature, the lower the strength. With the increase of curing time after high temperature, the strength of concrete gradually recovers, and the earlier the high temperature age, the higher the recovery degree, but the increase of strength recovery gradually decreases. 

Key words:  , concrete age, high temperature, compressive strength, split tensile strength