Experimental and numerical investigation of the behavior of self-curing R.C. flat slabs

Abstract

Self-curing concrete is one of the most notable enhancements in modern concrete technology. The study presents experimental and numerical investigations conducted to assess the effects of using self-curing concrete, highlighting the impact of the reinforcement ratio, and the size of the central square opening on the behavior of flat reinforced concrete slabs. Polyethylene glycol 400 is used to produce the self-curing concrete. The aim of this study is to investigate the impact of self-curing using polyethylene glycol 400 on RC flat slabs. Therefore, the experimental program in this study is implemented similarly to the parametric study of the research's experimental program (Heiza et al., 2005 [13]), in which high-strength RC flat slabs are cured using traditional curing by water. In addition, the experimental program is represented in the same sample dimensions, steel reinforcement ratios, and opening dimensions as in the parametric study, in order to compare the results, and evaluate the behavior of self-curing RC flat slabs in contrast with the behavior of those traditionally cured by water. The tested specimens are characterized into two groups; the first group contains five samples with different reinforcement ratios, as ρ varies from 0.43 % up to 1.08 %; and the second group contains five samples with central square openings of different sizes, with dimensions up to 400 × 400 mm. The experimental test results revealed that the increase in steel reinforcement ratio ρ increased the cracking load, failure load, and maximum deflection. Results also indicated that RC slabs with opening provided a reduction of 6.6–26.6 % in capacity, compared to RC slabs without opening. Moreover, a finite element model of the slabs was built using Abaqus 6.14, and validated by comparing its results with the test results, achieving a good agreement. The findings of this research confirmed the effectiveness of using self-curing concrete in casting the flat slabs to improve their behavior. Thus, the results of the present research are expected to be of great benefit to many countries facing water shortage, or rising temperatures, and seeking sustainable solutions to rationalize water resource consumption.