FLEXURAL STRENGTHENING OF REINFORCED CONCRETE WIDE BEAMS WITH DIFFERENT WIDTH OF CFRP

Abstract

Reinforced concrete wide beams (WBS) have been used in structural buildings to reduce floor heights, reinforcement congestion and facilitate the run of services under the floor. This paper presents the test results of four full-scale simply supported wide RC beams of (30 MPa) concrete strength under four-point bending up to failure in which their flexural behavior was studied. One of these was un-strengthened with carbon fiber reinforced polymer sheets (CFRPs), the three other beams were strengthened by using externally (CFRPs) bonded with epoxy with deferent width in flexural zone: beam strengthened with (30%) of cross-section width of beam, beam with (60%b) and beam strengthened with (100%b), The performances of the tested beams were measured as deflection, crack patterns, ultimate load, steel and concrete strains, and modes of failure. All beams with the same dimensions, reinforcement ratio and designed as under reinforced concrete (flexural failure). The test results showed that the strengthened beam with (60%b) provided the best flexural capacity as compared with the other strengthened beams. This beam increasing flexural capacity up to (29%) as compared with the control beam.