RESEARCH ON EARLY STRENGTH AND FREEZE-PROOF RESISTANCE OF AIR-ENTRAINED CONCRETE UNDER 3 ℃ CURING

The strength， the pore structure and freeze-proof durability of air-entrained concrete under 3 ℃ temperature curing and with different air contents were researched by taking air-entrained concrete under low temperature curing ( 3 0. 2) ℃ as the object，adopting strength test mercury intrusion method，pore analytical method and fast freeze-thaw method． The results showed that when concrete of 3 ℃ temperature curing，as the air content was increased，the distribution of pore diameter was uniform and the interior pore structure of concrete was improved significantly，however，the pore structure under the room curing at the same air content of concrete was lower than under 3 ℃ curing． In order to expound the influence of air content on the actual concrete strength in an even better fashion，the concrete compressive strength under 3 ℃ curing can further be estimated by pore structure， which was compared with the room curing actual compressive strength，showing the difference between the two．