Damages of Delay Curing Concrete on Strength

Abstract

The aim of treatment is to maintain as much as possible the concrete being saturated or close to saturation until the voids that were initially filled with water in the soft cement paste are filled with the required amount of hydration products. Therefore, delaying curing has negative effects on compressive strength. The resulting damages cannot be canceled even after compensating for the curing period. Many concrete structures are not treated for a sufficient period to ensure obtaining the required properties. The start of curing may also be delayed due to the presence of a holiday after the day of casting or relying on building guards who neglect Correct and adequate treatment. This research aims to study the effect of delaying the start of curing for a period of one, two, three, and four days after casting, in addition to studying the effect of changing the duration of curing with water, which includes 7, 14, and 28 days, on the compressive strength of concrete. The research includes the preparation of concrete cubes with dimensions (150 * 150 * 150) mm, and the mixing ratio was 1: 1.5: 3 with a water/cement ratio of 0.55. All samples were tested at the age of 28 days. The results showed that delaying the curing of concrete leads to a decrease in the compressive strength for a delay period of (1, 2, 3, 4) days, respectively, and that the greatest effect is when the curing is delayed on the first day, and that there is a significant increase in the compressive strength by 32.8% with an increase in the duration of wet curing. From 14 to 28 days, the concrete curing process must continue for a sufficient period to ensure that the concrete reaches the required design strength at the age of 28 days. Failure to comply with this period may have negative effects on the compressive strength of the concrete. In addition, increasing the duration of wet curing of concrete whose treatment is delayed is necessary to compensate for some loss in strength resulting from this delay, although it may not lead to the complete restoration of concrete properties.