关键词: 混凝土, 干寒大温差, 养护材料, 抗压强度, 抗裂性, 细观结构

Abstract: In an attempt to explore the most suitable curing material for the development of concrete in cold and dry environment with large temperature difference, we analyzed the compressive strength, crack resistance and microstructure of concrete cured by curing agent, rubber sheet and geotextile, respectively, and compared the properties with those under natural condition. Results revealed that in comparison with concrete cured under natural condition, (1) concrete cured with curing agent has inferior compressive strength but superior crack resistance, and in a mesoscopic sense, larger porosity and average chord length but smaller void spacing factor which are used to characterize the pore structure of concrete; (2) concrete cured with rubber sheet has better compressive strength but lower crack resistance, and in a mesoscopic sense, smaller porosity and average chord length but larger void spacing factor; (3) concrete cured with geotextile is endowed with the advantages of the abovementioned two curing methods, with enhanced crack resistance, porosity, average chord length as well as void spacing factor despite no big change in compressive strength, indicating that concrete cured with geotextile is of sound durability. In conclusion, among the four curing methods, geotextile is the most favorable for concrete development in cold and dry environment with large temperature difference.

Key words: concrete, cold and dry environment with large temperature difference, curing material, compressive strength, crack resistance, mesostructure