FREEZING AND THAWING RESISTANCE OF CONCRETE WITH INITIAL CRACK

Abstract

 Freezing and thawing resistance of concrete with an initial crack was investigated. The specimens were classified into plane concrete, fiber reinforced concrete, and reinforced concrete. In the tests of plane concrete with an initial crack, the crack grows seriously by the frozen expansion pressure of the water infiltrated into the crack, though the concrete material had high resistance to freezing and thawing. In the experimental results of fiber reinforced concrete, the long polypropylene fiber was useful to prevent the spalling of concrete cover, though the crack growth was not prevented. Moreover, in the experimental results of reinforced concrfete, it was shown that the crack growth was effectively prevented by steel reinforcing bar.