CURRENT PROBLEMS OF HARDENING MONOLITHIC ROAD AND AERODROME CEMENT CONCRETE CURING

Abstract

Studies of moisture loss from hardening monolithic cement concrete have been carried out. It was found that there is no consensus on the critical value of moisture loss from hardening concrete, at which shrinkage and cracking are possible, and there is no common understanding of the possible critical width of the shrinkage crack opening. It is shown that when the concrete hardens in air-dry conditions, its indicators, including durability, decrease by a factor of 2 or more. The critical value of moisture loss from hardening concrete was experimentally determined, which is 2 kg/m2. In this case, the deterioration of concrete properties as a result of rehydration of cement does not exceed 5 % and does not affect its durability. The possibility of restoring the properties of concretes, which were lost as a result of cracking during plastic shrinkage and contraction, has been experimentally proved if, after cracking, the concretes are placed for further hardening in a humid environment.