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As a result of the development of concrete structures, supplementary cementitious materials have become very important, particularly in structural engineering. Hematite powder, a common iron oxide (Fe2O3) found in rocks and soils, exhibits black, brown, and red colors. After treatment, it enhances the mechanical properties of concrete. This paper aims to highlight the influence of hematite powder on the behavior of high-strength RC deep beams. The experimental program consists of testing twelve deep beams under two symmetrical concentrated loads with different shear span-to-depth ratios of 1, 0.67, and 0.33. The deep beams are divided into three groups according to the shear span-to- depth ratio. Each group has four deep beams that differ in the proportion of hematite powder. Four replacement ratios of hematite powder were used in this study (0%, 1%, 1.5%, and 2%) based on the weight of cement. The experimental results showed that adding hematite powder by 1%, 1.5%, and 2% to the weight of cement increased concrete strength by 5.5%, 18.3%, and 4.16% respectively; splitting tensile strength by 37.8%, 63.4%, and 25.3% respectively; and increased concrete density by 1.86%, 3.4%, and 3.47% respectively. In addition, the experimental test results demonstrated that the ultimate load increases with a decrease in the (a/h) ratio and increases with increased concrete compressive strength. Diagonal crack width and mid-span deflection increase with an increase in the (a/h) ratio and decrease with an increase in concrete compressive strength.

来源平台：REVUE DES COMPOSITES ET DES MATERIAUX AVANCES-JOURNAL OF COMPOSITE AND ADVANCED MATERIALS