Influence of severe hot-dry climate on the mechanical properties of fibrous reinforced concrete beams

This paper presents the results of the work carried out to study the influence of curing environment and steel fiber volume fraction on the flexural strength, flexural rigidity, flexural toughness, and ductility of fibrous reinforced concrete (RC) beams. A total of twenty simply supported beams were tested. Ten of the twenty beams were cured under controlled laboratory conditions and the other ten were cured under severe hot dry climate (SHDC) characterized by their intense heat, Iow relative humidity, direct solar radiation, and large diurnal variations of daily temperatures. Tests were carried out 28 and 90 days after casting. Test results show that for non fibrous RC concrete beams the adverse effects of SHDC have more influence in reducing the flexural toughness than the flexural strength. On the other hand, test results indicate that under any of the two curing environment considered in this study, the flexural strength, flexural rigidity, flexural toughness and ductility of the fibrous RC beams are in direct proportion with the fiber content. Moreover, the results reveal that the enhancements in these engineering properties due to the steel fiber addition are not affected by the above described severe field conditions. Furthermore, inclusion of steel fibers in concrete helps, to some extent, in reducing the adverse effects of SHDC on the properties of concrete