الفهرس 
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Abstract
The development of Ultra High Strength Concrete (UHSC) started late in the 20th century by modifying some of the existing rules for designing concrete composition and selecting materials in High Strength Concrete (HSC) types. Beside ultra-high compressive strength (up to 200 MPa), UHSC also have considerably improved tensile strength, stiffness and durability compared to other concrete types. Therefore, they are also called ultra high performance concretes (UHPC). Ultra high strength concrete (UHSC) finds wide use in tall buildings, bridges, airports, power plants etc.
This research work investigates the production of UHSC using different local materials in Egypt, studies the different fresh and hardened properties of the produced concrete. It also investigates the flexural behavior of beams cast with the produced concrete. In addition, the research includes a theoretical study for predicting the flexural behavior of concrete beams cast with ultra high strength concrete and comparing it with the experimental results
An experimental program undertaken at the Housing and Building Research Center, (HBRC) to study the behavior of ultra high strength concrete beams The program consists of a total of twelve RC beam specimens, were tested and divided into three groups:
The first group consists of three HSC beams with compressive strength 60 Mpa 80Mpa one of them without steel fiber and other two with steel fiber and reinforcement ratio 1% with section (10*25) cm
The second group consists of UHSC five beams with compressive strength 120Mpa with many of reinforcement ratio 0.7% ,1% ,1.4% ,1.8% ,2.2% with section (10*25) cm.
The third group: consists of four beams with UHSC 120 Mpa with fiber two of them with
1%, 1.2% reinforcement ratio and (10*20) cm section and others with 2%, 1.8%
reinforcement ratio and (10*30) cm section
The beams were tested under monotonic flexural loading up to failure. An analytical to evaluate the performance of UHSC beams under the effect of flexural loading by using a finite element model. The analytical program will be analyzed using the finite element model in the evaluation of flexural capacity of the UHSC beams. Results will be compared to those of the experimental program.