Civil Eng. Dep. at UOT discussed M.Sc. thesis about:

Behavior of Reinforced Recycled Aggregate Concrete Column Strengthened With CFRP 

The thesis of the student (Anwar Ch. Jabr) of Structural Eng. Discipline, included conducting an experimental study to verify the behavior of high-strength circular bound and spiral concrete columns containing recycled aggregates reinforced with carbon-fibre-reinforced polymer or by adding steel fibers and subjecting them to axial load until failure. Twenty column samples 150 mm in diameter x 600 mm in height with linear rebar ratio ρ = 0.017 were cast and tested under the same conditions. Variables considered include replacement percentage of recycled concrete aggregate 0, 50, and 100%, CFP external confinement ratio 0, 25, 50, and 100%, type of cross-reinforcement, bonded or spiral reinforcement, and volume percentage. For steel fibers added 0, and 1.5%.

The experimental results showed that the strength of concrete decreases when the proportion of recycled coarse concrete aggregate is increased; Therefore, the final load capacity of the shaft decreases. In contrast, the maximum load capacity of the shaft is increased when the external confinement is increased by carbon-fibre-reinforced polymer, screw reinforcement rather than bonded reinforcement, and when steel fibers are added to concrete containing recycled aggregates. Also, the reinforcement of the shaft samples using carbon fiber reinforced polymer or steel fibers reduced the longitudinal and lateral displacements at the same load values ​​for the threaded and threaded shafts.

The discussion committee consisted of:-

• Prof. Dr. Iyad K. Saihoud / the head.
• Prof. Dr. Asmaa A. Ahmed / member.
• Prof. Dr. Raed F. Abbas / member.
• Prof. Dr. Qais A. Hassan / supervisor.
• Prof. Dr. Diaa H. Mohammed / supervisor.