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Reinforced concrete deep beams are structural members having depth much greater than normal in relation to their span, while the thickness in the perpendicular direction is much smaller than either span or depth. The strength of deep beams is usually controlled by shear, rather than flexure. In this study, the previous researches related to reinforced concrete deep beams will be reviewed. These researches approximately started in the second half of the past century. Large numbers of researchers studied the behavior of concrete deep beams and the determination of their capacity. Some of these researches are experimental investigations carried out by testing a number of deep beams with variation in some parameters, while the others are theoretical to estimate deep beam capacity by developing some theories and suggestion of equations for calculating its capacity and comparisons were made with those adopted by some codes. Because of the large number of these researches, their review requires large part of this study, and because the prior studies elaborately reviewed the pioneer researches, only the researches made since year 2000 will be reviewed in this study.

Background: Over the last three decades, the interest in using advanced high-performance materials in the construction industry has been increasing worldwide. Recently, a very high strength cement-based composite with high ductility called Reactive Powder Concrete (RPC) has been developed. The RPC concept is based on the principle that a material with a minimum of defects such as micro-cracks and voids will be able to achieve greater load-carrying capacity and durability. Methods: In the present paper, an experimental program of sixteen reinforced concrete one-way slabs was conducted to investigate their behavior under flexural loading. Four of these slabs were with Normal Concrete (NC) and the others of Modified Reactive Powder Concrete (MRPC). All slabs were identical in the dimension of its length and width (1000×500) mm, respectively, and its thickness was varied as one of the variables used in the present work. Other parameters for a one-way slab are concrete type, steel fibers content and flexural steel reinforcement ratio (0.33 and 0.66)%. Results: The results showed that the MRPC slabs with steel fibers failed in a ductile manner and had ultimate load capacity more than that of non-fibrous MRPC with an improvement percentage that reaches up to (66) %. This percentage became (212) % in comparison with normal concrete slabs. Conclusions: Moreover, the results showed that slabs, for both concrete types, reinforced with lower steel ratio failed by tension mode, otherwise, the slabs of higher reinforcement steel ratio failed by combined tension-shear mode. However, an improvement was observed in the ultimate load capacity up to (53 and 98) % when the ratio of steel reinforcement and slab thickness increased, respectively.

Glass-fiber-reinforced polymer (GFRP) bars reinforced concrete beams and fortified by carbon-reinforced polymer (CFRP) slips can provide high resilience, high sustainability and reasonable strength for a building scheme. Few experiments contract the combined operation of these products and this was the undertaking's fundamental impetus. The presented study includes an extensive and interesting experimental analysis of the flexural efficiency of reinforced concrete beams GFRP bars and fortified by CFRP sheets. A total of ten GFRP reinforced concrete beams are equipped, experienced and subject to frequent loading series using a four-point bending expedient to complete a catastrophe analysis. The main parameters were GFRP reinforcement ratio and number of CFRP sheets. The central deflection, crack size and concrete strains of the verified beams were verified and contrasted. In this study, the feasibility of using particle image velocimetry (PIV) to detect cracks established in reinforced concrete beams were discovered so that a practical effect can be suggested. The PIV technique has been realistic for analyzing the surface field movement and strain. The test results discovered that the crack sizes and central deflection were considerably decreased by increasing the reinforcement ratio and number of CFRP layers, results characterized that due to its lower cost and strong capacity to observe cracking efficiency, PIV method can be used as a substitute for traditional measuring methods during specific structural tests, exclusively in bending tests.

Improvement the mechanical properties (compressive and flexural strength) of low, normal and high strength concrete (LSC, NSC and HSC) was investigated experimentally in this work by used CFRP sheets and steel fibers. The experimental program of this research was consisted of two parts, first part was aimed to evaluate the effect of confinement by CFRP sheets on the compressive strength on the cubes and cylinders, while the second part was investigated the effect of strengthening by CFRP sheets, adding steel fibers and use both on modulus of rupture. Comparison with unconfined specimens, results show that the confinement by CFRP was increased the cube compressive strength about 208, 47 and 27% for LSC, NSC and HSC, respectively, while the increasing in cylinder compressive strength was 216, 64 and 51%. On the other hand, increasing in modulus of rupture for LSC was 373.93, 84.83 and 506.6% for specimens with CFRP, steel fiber and both used of CFRP with steel fibers, respectively. While this increasing for HSC was 575, 128.2 and 725.64% for CFRP, steel fibers and both used of CFRP with steel fibers, respectively. However, for NSC, the percentage of increasing was 455.7, 73 and 605% for the same order.

The solution of using glass fiber reinforced polymer (GFRP) bars, as reinforcement in concrete structures to overcome the problems created by steel corrosion, is now widely accepted because of both its non-corrosive nature and good results shown by large investigation efforts. In this paper twenty tests had been conducted on reinforced concrete wall specimens of (800 mm height x 450 mm width x 50 or 70 mm thickness effective dimensions). Four specimens were reinforced with steel bars to be considered as References, while the others were reinforced with GFRP bars. The specimens were made using normal and high strength concrete. All specimens showed similarity in the structural behavior and load pattern, the results show that Steel reinforced walls have 28% higher ultimate load than corresponding GFRP reinforced walls, also an approximate linear increase in the failure load with increasing in flexural GFRP reinforcement in range from 40.4% to 98.8% for NSC walls and in range of 70% to 115.1% for HSC walls. The ductility of the specimen reinforced with GFRP bars is 46% higher than that of steel reinforced specimens.

This paper deals with a numerical simulation of reinforced concrete square columns. The behavior of reinforced square columns of normal and high strength concrete was studied, and special attention paid to the concrete strength, ratio of longitudinal steel reinforcement, as well as reinforcement steel grade of this type of columns. In the present study, ABAQUS program was utilized to represent the response of this type of columns. The numerical model of finite element employs the approach of damaged plasticity for concrete. For effectiveness, a column of reinforced concrete was represented that had been comparison with experimental results that presented from the other researchers. In this research the numerical results were done for three types of loading, columns subjected to pure compressive force only (compression failure is done), columns undergo bending moment only (tension failure is done), and finally columns under axial load as well as bending moment such that the tension and compression failure is done at same moment. An interaction equation was derived in this research and can be applicable for any section of columns. The present equation was appeared a very good results when compare its interaction diagram with interaction diagram driven from previous works.

This research is devoted to investigate the experimental and theoretical behavior of deep beams under monotonic two points loading. An experimental program examining six RC deep beams is carried out. The investigated parameters include shear span to depth ratio varying from 1.0 to 0.276. A comparative study is conducted in this paper by using finite element software ANSYS. The experimental and numerical results show that concrete strength and shear span to depth ratio are the two most important parameters in controlling the behavior of RC deep beams. Comparison of experimental results was made with corresponding predicted values using the Strut and Tie procedure presented ACI 318M-11Code and with other procedures mentioned in the literature. It was found that the Strut and Tie procedure presented in ACI 318M-11Code give conservative results as compared with the experimental tested results. The results showed reliability of analysis in predicting deep beams behavior in terms of failure load, failure mode as well as crack propagation.