Title: REINFORCING BRIDGE I-GIRDERS USING CFRP SHEAR STRIPS

Author(s): Rico J. Massa, William D. Cook and Denis Mitchell

Publication: Symposium Paper

Volume: 328

Issue:

Appears on pages(s): 1.1-1.20

Keywords: shear; shear strengthening; CFRP; crack widths; prestressed concrete; bridge girders

DOI: 10.14359/51711145

Date: 9/12/2018

Abstract:
An experimental program was carried out on full-scale precast pretensioned I-girders to study the influence on the shear response of carbon fiber reinforced polymer (CFRP) shear strips epoxied to the sides of the girders. The test program demonstrated that the CFRP shear strips were effective in increasing the shear strength of the webs and in controlling the shear crack widths. The shape of the I-girders makes it difficult to properly anchor the vertical shear strips. The curved epoxy transitions between the web and the flanges at the re-entrant corners together with the use of horizontal CFRP strips in the regions of the re-entrant corners helped to improve the anchorage of the vertical CFRP strips. The shear resistance components from the concrete, the stirrups and the CFRP shear strips, were determined experimentally and compared with analytical predictions. The results from this experimental study are compared with the test results from other researchers. The design approach of the 2014 Canadian Highway Bridge Design Code provides conservative estimates of the shear strength of the webs.