Title:
Strengthening of Cantilever and Continuous Beams Using New Triaxially Braided Ductile Fabric
Author(s):
Nabil F. Grace, Wael F. Ragheb, and George Abdel-Sayed
Publication:
Structural Journal
Volume:
101
Issue:
2
Appears on pages(s):
237-244
Keywords:
concrete; ductility; flexural strengthening; polymer
DOI:
10.14359/13021
Date:
3/1/2004
Abstract:
This paper deals with the effectiveness of a new triaxially braided ductile fiber-reinforced polymer (FRP) fabric for flexural strengthening of cantilever and continuous reinforced concrete beams. Two series of beams were experimentally investigated. The first series included beams with one overhanging cantilever strengthened in flexure and loaded with one concentrated load at the end of the cantilever. The second series included continuous beams with two spans strengthened in flexure along their positive and negative moment regions and loaded with a concentrated load at the middle of each span. One beam in each series was not strengthened and was tested as a control beam. The behaviors of the beams strengthened with the new fabric were investigated and compared with the behaviors of similar beams strengthened using a commercially available carbon fiber sheet. The responses of the beams were examined in terms of deflections, strains, and failure modes. The beams strengthened with the new fabric showed greater ductility than those strengthened with the carbon fiber sheet. The new fabric provided reasonable ductility due to the formation of the plastic hinges that allowed for the redistribution of the moment between the positive and negative moment zones of the strengthened continuous beam. Redistribution of the moment enabled the full use of the strength of the beam at cross sections of maximum positive and negative bending moments.