Abstract. This paper presents results of an experimental study for the shear strengthening of reinforced concrete (RC) deep beam using near surface mounted (NSM) carbon fiber reinforced polymer (CFRP) anchor bars. To ensure shear failure, five RC deep beam specimens were cast with nominal shear reinforcement. Shear strengthening of the RC deep beams was conducted by inserting 5 mm diameter by 450 mm length of CFRP bars as anchors with spacing of 100 mm and 150 mm centre to centre from the support of the beam. All RC beams were simply supported and subjected to a four-point bending test with shear span to effective depth ratio of 0.864. The results presented include the ultimate load, CFRP contribution to shear, modes of failure and the load-deflection profile. The shear enhancement of the RC deep beams shows an increment of 17.3% up to 25.5% with decreasing mid-span deflection from 6.4% to 15.1%. In addition, using this technique also increases its flexural beam resistance under the same conditions.

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The adding of silica fume to mix is becoming a huge benefit due to an improvement of mechanical properties. The percent of adding is very important to get targeted mechanical properties. This study investigates the behaviour of polymer modified concrete (PMC) modified with different percentages of silica fume as a percentage of cement weight. Using silica fume powder leads to improve the behaviour of the stress-strain diagram until 10% from the weight of cement, and to increase the values of modulus of elasticity. More dosages of silica fume decrease the modulus of elasticity. The modulus of elasticity increased from 27932 MPa for reference mixes to 43029 MPa for mixes having 10% silica fume powder. Also the of flexural strength increases by increasing silica fume to 12.5%, then after this value is dropped. All of the tensile strength, flexural strength, and modulus of elasticity have been studied in this investigation.

This paper presents experimental results of four prismatic concrete reinforced beam and strengthened by NSM (Near surface mounted) FRP (Fiber Reinforced Polymer) reinforced technique, with additional roots planted in the concrete. The strengthening technique causes load capacity of beams to increase from (6%-8%).A decrease in mid-span deflection was also observed from (4%-5%).Using this technique gave increasing in flexural beam resistant under the same conditions and this increasing was also noted in shear beam resistant.

This paper presents experimental results of four prismatic concrete reinforced beam and strengthened by NSM (Near surface mounted) FRP (Fiber Reinforced Polymer) reinforced technique, with additional roots planted in the concrete. The strengthening technique causes load capacity of beams to increase from (6%-8%).A decrease in mid-span deflection was also observed from (4%-5%).Using this technique gave increasing in flexural beam resistant under the same conditions and this increasing was also noted in shear beam resistant.