ABSTRACT

The effect of the entrainment of a minor amount (4-6% by volume) of air on the ability of concrete to withstand freeze-thaw cycling is remarkable [3] and is illustrated in Fig. 3.1.

Air entrainment of concrete carriageways, aircraft runways, and parking garages is now accepted as normal practice and several hundred thousands of cubic meters of this type of concrete have been placed. In North America the use of air-entrained concrete is universally accepted and therefore finds greater use than in Europe.