关键词: 孔结构;强度;抗渗性

Abstract: The effects of pore structure parameters on early strength and impermeability of air-entraining concrete at 28 d and 56 d under low temperature(3 ℃)were studied.The results show that with the increasing of air content, the porosity increases, the concrete strength decreases gradually, and the impermeability decreases first and then increases.When the amount of air entraining agent is appropriate, the spacing factor of concrete is the best, at this point, the permeation path of chloride ion becomes longer;under low temperature(3 ℃)condition,the pore size distribution of the concrete degrades,and the main pore size distribution range of the concrete increases obviously; finally, with the growth of concrete age,pore size of concrete develops towards the tendency that large hole decreases, small hole increases,but the development seed is relatively slow.

Key words: pore structure;compressive strength;impermeability