关键词: 干寒;大温差;混凝土;抗裂性;抗压强度;孔径分布

Abstract: Cracking process , compressive strength and 28 d pore size distribution of concrete were studied in a certain environment of dryness-coldness and large range of temperature , and the relationship between initial cracking area , pore structure and compressive strength of concrete was analyzed , and compared with the results of standard curing .The results show that in a certain environment of dryness-coldness and large range of temperature , the crack resistance and mechanical properties of concrete are worse than it is in standard curing , more concretely , the initial cracking time is shorter , the initial crack length and the crack width are larger and the total number of cracks is more .In the same curing duration , the compressive strength of concrete is smaller than that which is in a standard curing , and there is a certain correlation between compressive strength and initial cracking area of concrete .Morever , there are some differences in the pore size distribution .The main performance is that the small holes is fewer , the largeholes is more and the pore size distribution moves towards the large aperture .In addition , the water to binder ratio also has an effect on the crack resistance , compressive strength and pore size distribution of concrete.

Key words: dryness-coldness;large range of temperature;concrete;crack resistance;compressive strength;pore size distribution