Influence of Internal Curing on the Mechanical Properties of Normal Strength Concrete

Abstract

The current study investigated the influence of internal curing on the mechanical properties of normal concrete produced at the Islamic University of Gaza (IUG) laboratories. Due to the high aborption capacity of the local broken pottery fragments, crushed pottery material was utilized in this study as the internal water storage source. The specific gravity and the absorp-tion capacity of the crushed pottery (CP) sieves were identified to ensure the suitability of such material. The current study investigated the partial replacement of 0%, 10%, 15%, 20% and 25% of fine aggregates with CP material. Slump tests were carried out for the CP smaples to obtain the effect of various contents on the workability of the mixes. The CP specimens were also prepared to obtain the mechanical properties, including the compressive strength and flexural strength. The com-pressive strength of the samples was obtained at ages of 7, 14 and 28 days. The optimum CP content was identified and applied to study the flexural strength. The results of the experiments showed that the use of the locally available crushed pottery as an internal curing material was effective in curing the concrete samples. The partial replacement of the natural fine aggregates with various contents of CP was also positive for the slump values. Further, the application of CP material was successful in improving the early compressive strength and flexural strength. A slight improvement in the 28-days strength results was revealed with the increasing content of CP. The slump and strength results indicated that 20% partial replacement of fine aggregates with CP materail was the optimum.