الفهرس 
(INTRODUCTION)Only 14 pages are availabe for public view
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Abstract
Six beams reinforced with GFRP bars were initially casted and tested in three point loading; the GFRP bars had a fixed nominal diameter of 9.64 mm, tensile strength of 550 MPa and elastic modulus of 48 GPa. The compressive strength of the concrete mix was 30 MPa, the strain gauges and the LVDTs were fixed in place and the tensile and compressive strains and the deflection along the beam span were measured. All the beams failed due to sudden brittle failure at the load position. The load-strain relations were presented with the strain profile along the height of the beams and the load- maximum deflection curves of the beams.
Three beams were retested as there was slippage of the bars at the end of the beam, so the beam ends were casted by non-shrinkage grout and these three beams were re-tested with reduced span and with shear span to depth ratio less than 1.5 to decrease the stresses on the bars and it was found that the failure mode did not change. A comparison of the test results and the experimental failure load with the flexural capacity, shear capacity and cracking load of the beams was done and it was found that the experimental load was less than the flexural capacity of the beams and less than the shear capacity computed from equations (5.6) to (5.10).
Then the experimental load was compared to the cracking load of the beams and it was found that three of the beams failed at approximately the cracking load while the other beams failed at a load level higher than the theoretical cracking load of the beams. Then an analysis of bond between the used GFRP bars and the concrete was conducted and it was found that the bond stress calculated from the pull-out test results was less than the bond strength calculated using different equation, thus it was realized that the bond between the bars and the concrete had a strong influence in the failure mode that occurred in the tested beams.