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Crushed Over-Burnt Clay Bricks (COBB) is a promising alternative to the natural gravel aggregate in Lightweight Concrete production because of its high strength-to-weight ratio. In addition, COBCB is considered a green aggregate by solving the problem of disposing of this solid waste. in this paper, a total of fifteen Reinforced Concrete beams were constructed and tested up to failure. The experimental program was classified to five groups, the first group was casted with Normalweight Concrete (NWC) as control, the remaining four groups were casted with LWC. The test parameters were concrete type, reinforcement ratio and silica fume (SF) content. The behavior of beams was evaluated in terms of crack patterns, failure mode, ultimate deflection, and ductility. Based on the experimental results, the resulting concrete showed that it satisfies the requirements of LWC in terms of unit weight and strength. In addition, increasing the reinforcement ratio and silica fume content increased overall beam performance. The results revealed that measurable enhancements to the majority of the performance characteristics of LWC beams by adding SF. Thus, using COBCB as a coarse aggregate has successfully been used to produce good quality lightweight concrete. Both ACI 318-14 and CSA-A23.3-14 give acceptable for predicting cracking moment, ultimate capacity and and mid-span deflection.

This study is mainly focused on the behavior of continuous concrete slabs reinforced with hybrid bars. Moment redistribution is a specific phenomenon in statically indeterminate structures due to the existence of redundant constraints and non‐uniform flexural stiffness of the reinforced concrete (RC) members. In this paper, a numerical one‐factor‐at‐a‐time parametric study was conducted using ABAQUS software to intensely understand the impact of several parameters on the performance of the hybrid RC continuous slabs. The investigated parameters were reinforcement type and ratio, FRP‐to‐steel ratio, and arrangement of reinforcement. The analysis results showed that the difference between sagging and hogging axial stiffness is the most influential parameter on the moment redistribution of hybrid‐RC continuous slabs. In addition, increasing the amount of reinforcement ratio at the mid‐span section is more effective in enhancing the load capacity of the slabs than over middle support section. Based on the obtained numerical results, some modifications to the Tarek et al. equations were proposed to be valid for hybrid‐RC continuous slabs. The presented modifications yielded good agreement with the numerical results predicting the moment redistribution of continuous concrete slabs with hybrid reinforcement.

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