In this study, a new shear strengthening technique for reinforced self-compacting concrete (RSCC) deep beams was suggested and compared with some traditional techniques. An experimental test program consists of sixteen specimens of RSCC deep beams strengthened by different materials such as steel, glass, and carbon fiber reinforced polymers (GFRP and CFRP) was executed. Externally bonded layers (EBLs) and near-surface mounted reinforcement (NSMR) were used as two different techniques. The effects of the new technique which depends on using intertwined roving NSM GFRP rods saturated with epoxy were compared with the other models. The new technique for shear strengthening increases the load capacity from 36% to 55% depending on the anchorage length of GFRP rods. Two-dimensional nonlinear isoperimetric degenerated layered finite elements (FEs) analysis was used to represent the SCC, reinforcement, and strengthening layers of the tested models. The analytical results have been very close to the experimental results. 1. Introduction Reinforced concrete (RC) deep beams were often used and encountered in many structural applications such as diaphragms, bridges, water tanks, precast and prestressed construction, foundations, silos, bunkers, offshore structures, and tall buildings [1, 2]. Deep beams are widely used as transfer girders in offshore structures and foundations. with the strong growth of construction work in many developing countries, deep beam design and its behaviour predication are a subject of considerable relevance. Many experimental studies have been performed to investigate the behavioral characteristics and the cause of the shear failure of RC beams [3–5]. Several researchers [6–8] and the current codes [9–11] have recommended the design of deep beams using the strut-and-tie model. In these strut-and-tie models, the main function of shear reinforcement is to restrain diagonal cracks near the ends of bottle-shaped struts and to give some ductility to struts. Thin deep girders often contain congested shear reinforcement within the web, the normal concrete often does not flow well when traveling through the web and does not completely fill the bottom bulb. This results in voids in the concrete finish, which often termed bug holes or a honeycombing effect in the finished concrete surface. In this case, many researches recommended the use of self-consolidating concrete (SCC) [12–14]. Self-consolidating concrete, also known as self-compacting concrete, yields distinct advantages over typical concrete due to its liquid nature such as (a) low noise
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