Abstracts Category : Other

Flexural Strengthening of RC beams using Fiber Reinforced Cementitious Matrix, FRCM

by Abdulla Jabr

The use of externally bonded Fiber reinforced polymer (FRP) sheets has been successfully used in the repair and strengthening of both the shear and flexural capacities of reinforced concrete (RC) beams, slabs and columns since the 90's. However, the externally bonded FRP reinforcements still presents many disadvantages, such as poor performance in elevated temperature and fire resistance, lack of permeability, and strength degradation when exposed to ultraviolet radiation. To remedy such drawbacks, fiber/Fabric Reinforced Cementitious Matrix (FRCM) has been recently introduced. The FRCM system consists of fiber mesh or grid embedded in a cementitious bonding material. The present research investigates the flexure strengthening of reinforced concrete (RC) beams with FRCM. The experimental testing included sixteen large scale concrete beams, 150 mm x 250 mm x 2400 mm, internally reinforced with steel bars, and strengthened in flexure with FRCM. The investigated parameters were the effect of axial stiffness, internal steel reinforcement, and the concrete strength. Two steel reinforcement ratios of 0.18 and 0.36 of the balanced reinforcement ratio as well as three FRCM systems using, Glass, Carbon and PBO (Polyparaphenylene benzobisoxazole) fibers were investigated. Test results are presented in terms of load-deflection, load- strain and load-crack width relationships. The test results indicated that the PBO-FRCM significantly increased the ultimate capacity of the strengthened RC beams compared to the glass and carbon FRCM.Advisors/Committee Members: Ghrib, Faouzi, El Ragaby, Amr.