الفهرس 
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Abstract
An experimental program was conducted including eight reinforced concrete two-span
continuous deep beams. All tested beams were fabricated, instrumented and then tested to failure
under the effect of two concentrated loads one being placed at each span. Seven beams were
made using high strength concrete whereas one beam was made using normal strength concrete.
The main objective of this study was to investigate the behavior of two-span continuous deep
beams within the whole range of loading starting from the elastic range up to the failure of each
beam. Many significant factors were considered such as: concrete strength, size, shape and
location of openings being placed within the interior shear spans. Furthermore, the effect of
strengthening of two-span continuous deep beams on its behavior was considered in the case of
beams provided with openings within the interior shear spans. The strengthening technique
considered was ’bonding exterior carbon fiber reinforced polymers (CFRP). Different
strengthening schemes were considered including bonding CFRP strips in the horizontal and
vertical directions around the openings. For all tested beams, deflections, strains in the
longitudinal flexural reinforcement, and strains in the vertical stirrups were measured and
recorded. Also, the initiation and propagation of cracks were recorded. Cracking patterns and
failure modes were observed. Cracking loads and failure loads were recorded. Test results
revealed the significant effect of the concrete strength and the presence of openings on the shear
behavior of tested two-span continuous deep beams. Such behavior was also affected by the
shape and size of the openings. Furthermore, it was found that strengthening of those deep beams
with openings by bonding CFRP strips resulted in about 20% enhancement in the beam failure
load in comparison to non-strengthened beams. However, the failure load of strengthened deep
beams is still less than that of solid beams by about 20%.
Finally, tested beams were theoretically analyzed using strut-and-tie method. To achieve
that, a commercially available program ”CAST” was used. Theoretical results were compared to
the experimental ones.