The Effect of FRP-Confinement on Compressive Strength of Polypropylene Fiber Concrete Specimen

Using fiber-reinforced plastic (FRP) to retrofit reinforced concrete columns is an impressive way. In this research, the effects of using 1.2 kg/m3 micro monofilament polypropylene fibers of 12-millimeter length on compressive strength of Specimen confined by FRP are studied. Upon mechanical and chemical tests on materials, the best mix plan is chosen followed by making one cubic meter of concrete prepared in batching machine. Half of the concrete was made with polypropylene fibers while the other half did not contain any fibers. As many as 24 cylindrical samples of 150*300 mm were taken from each. Composite coir fibers were used to increase bearing strength and for confinement. The samples were tested under axial static loading and were compared using their load-displacement curves. The results show that FRP-confinement improve mechanical properties of polypropylene fiber concrete including concrete stiffness, compressive strength, ultimate strain and ductility index and also delayed the final break.