Shear Strengthening of High Strength Reinforced Concrete Beams Using Fibrous Composites

Journal Article
J., Shannag, M. . 2004
Publication Work Type: 
Research, Magazine of Concrete Research
Issue Number: 
7
Volume Number: 
56
Pages: 
419-428
Publication Abstract: 

A series of seven rectangular high strength concrete beams was tested under third point loading to study the effectiveness of using externally applied high strength steel fiber reinforced concrete jackets (SFRC) as a method of strengthening shear deficient high strength reinforced concrete beams. The overall response of the beams loaded up to failure, the onset of cracking, and crack development with increased load and ductility were described. Two types of steel fibers were used, brass coated and hooked end with fiber content ranging from 1 to 4% and an aspect ratio of 40 and 60 respectively. The test results indicate that all beams strengthened with SFRC jackets displayed excellent shear behavior. The ultimate shear strength of the strengthened beams was much higher (about 60%) than that of the reference beams, depending on the energy absorbed in debonding and stretching the fibers. The use of SFRC jackets transformed the mode of failure into a more ductile flexural one. A design procedure is suggested for a more accurate prediction of the shear capacity of the strengthened beams.