الفهرس 
CHAPTER (1) NTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The existence of transverse openings in the web of reinforced concrete beams is usually used to provide paths for required ducts and pipes which are necessary to accommodate essential services like water supply, sewage, air-conditioning, electricity, telephone, and computer network. However providing an opening in the
beam reduces its stiffness, which decreases the overall strength. The provision of openings through the beam depth, changes its simple mode of behavior to a more complex one depending on the size, shape and location of openings. Therefore, the
design of such beams needs special handling, which falls beyond the scope of the most building codes.
Many investigations were conducted to study the use of steel and FRP materials as strengthening materials in solid beams in case of flexural and shear stresses. Only a few literatures were found related to the strengthening of beams with openings. Repair and strengthening of an existing structure may be essential in many cases such as increasing the stiffness of the beams due to making transverse openings in the web of
beams after construction, especially when loads are expected to be increased than the design loads as a result of changing the usage of the reinforced concrete building.
An experimental test program of fourteen reinforced concrete beams of identical dimensions and reinforcement. Beams have large central or side openings. These
specimens were strengthened using steel or CFRP plates by different techniques and tested under four point bending test to study and compare the shear and bending behavior of beams with large openings before and after strengthening.
Reinforced concrete beams with openings were modeled before and after
strengthening using the nonlinear finite element program, ANSYS, to predict and analyze the behavior of specimens with openings.
The nonlinear analysis includes the stress strain relationships for the different materials, crushing, and propagation of cracks. The finite element results are also compared and verified with the experimental results.
The main conclusions and recommendations were summarized and discussed. The research shows that the methods of strengthening using CFRP sheets were better than the traditional method using steel plates.