الفهرس 
The research objectiveOnly 14 pages are availabe for public view
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Abstract
Until recently, high strength concrete was usually specified only for projects where special vibration or other special manufacturing processes were available as in the precast or the prestressed concrete industry. In the last 10 to 15 years, there is growing interest in using high strength concrete ready mixed or site mixed concrete cast in place structures in many projects over the world such as high buildings, power stations, bridges.
Tunnels….etc. Many experimental studies have been conducted in recent years to strengthen flexure members of high strength concrete by using various materials to provide sufficient flexure mode of failure.
The main objective of this research is to study the flexural behaviour of high strength concrete beams reinforced with new composite materials.
Twenty four beams were cast in this research. One mix was used for casting the beams. Chemical admixtures were used in concrete mix were silica fume and fly ash as a partial replacement of cement content, high range water reducing admixtures (Sikament-NN) was used as an addition of cement content and fiber mesh was used as an addition of cement content.
The behaviour of the twenty four beams was investigated through the effects of many variables:1- The type of beams reinforcement (control beams, beams reinforced with expanded metal mesh, beams reinforced with welded metal mesh and beams reinforced with fiberglass mesh).
2- The shape of beams (rectangular and U-shape beams).
3- Using U.P.V.C pipes with external diameter 48.25mm and 40mm for rectangular and U-shape beams respectively.
The mechanical properties were performed in this research to investigate the behaviour of the twenty four high strength concrete beams were deflection, rotation, initial cracking load, number of cracks, failure load, flexural serviceability load,
ductility ratio, energy absorption and strain.
The experimental results of this research show that:
1- Using fibers in concrete mix improved the mechanical properties of high strength concrete beams.
2- Using expanded metal mesh or fiberglass mesh as a reinforcement was given better results than using welded metal mesh as a reinforcement.
3- The mechanical properties of rectangular beams were better than that of U-shape beams.
4- Using U.P.V.C pipes or light bricks leading to deterioration of the mechanical properties of high strength concrete beams.