الفهرس 
Acknowledgement
IntroductionOnly 14 pages are availabe for public view
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Abstract
Maintained reinforced constructions also subjected to harsh environmental conditions and working loading conditions like earthquakes, tornados, storms, traffic accidents, corrosion, and wind loads which can damage these previous cured failures. Modern construction failure maintenance methods become more and more an important issue because of the trend to build more complex architecture designs and the increase of the design loads and altitudes in the modern constructions. These failures produce large losses in lives and money. Most of modern construction is made from reinforced concrete which become the main material for modern constructions and widely used in civil constructions such us buildings, dams, bridges, etc.
In consequence, the importance of concrete repair in the field of concrete construction leads to increasing demands for knowing the mechanical behavior of this construction repair. Epoxy resin is one of the most commonly material used to repair cracked concrete.
These repaired constructions are mostprobably to be subjected to dynamic loads however, these kinds of loads are difficult to study and simulate in lab. Hopkinson split pressure bar is the only test apparatus that can cover the range of dynamic loading that need to be studied with adequate accuracy because of the nature of its measuring system that element stress wave superposition opportunity. The measuring system consists of ( a striker bar, incident bar, the transmitted bar, two strain gauges station positioned at the middle of the incident and transmitted bar, damper to absorb the rest of the stress wave). Hopkinson can cover higher strain rates that can reach. The split Hopkinson pressure bar arrangement was loaded using an air operated gun. In this work a cylindrical concrete specimen with centered through hole in which a steel bar (corrugated or threaded or threaded) installed in it using epoxy adhesive for fitting. The specimens were tested both statically and dynamically to cover the whole range of loading. The fractured specimens; surfaces were examined carefully to understand the mechanism of failure and the role of each of the compounds in tghe failure process.