Internal curing for mitigating high temperature concreting effects

Abstract

It is widely accepted that high temperature during casting of concrete causes damage on the material microstructure. Several of the most prominent drawbacks of high temperature concreting include the increased water demand, slump loss, drying shrinkage, autogenous shrinkage, decreased mechanical and durability properties. The accelerated drain of capillary pores due to intense drying or rapid cement hydration (increased self-desiccation) may induce stresses within the material’s structure.The current research aims to mitigate high temperature concreting effects using internal curing (IC). Highly-absorptive normal weight aggregates (HANWA) were employed to deliver IC water. The investigated parameters included various cast temperatures, age, curing regimes and type of aggregates. A number of mechanical and durability properties were measured to assess the effectiveness of the proposed methodology of IC. It was shown that the employment of IC had a beneficial effect in all measured properties. This was more evident in the specimens exposed to adverse environmental conditions.