International Concrete Abstracts Portal

Title: Flexural Behavior of Mechanically-Fastened FRP-Strengthened Concrete Members

Author(s): Vicki L. Brown, Andrew Dinh, and Giovanna Iacono

Publication: Special Publication

Volume: 275

Issue:

Appears on pages(s): 1-20

Keywords: Concrete beams; Fiber reinforced polymers; Flexural strengthening

Date: 3/1/2011

Abstract:
The behavior of seventeen RC beams strengthened with FRP laminates mechanically fastened to their tension soffits with concrete anchor bolts is presented. The beams were tested in four-point bending on a 7.5 foot (2286 mm) span. Bolt diameter and spacing and FRP strip length were varied. The beams exhibited increases in yield moment ranging from 12.5% to 46%, and increases in ultimate moment from 30% to 75%, while displacement ductility ratios were 75% of values from un-strengthened control beams. The number of fasteners in the shear span had a greater impact on ultimate strength than did FRP strip length. Terminating the FRP strips in regions of larger bending moment resulted in an unexpected change of failure mode from concrete compression to shear. Measured strains in the FRP were less than those calculated assuming fully bonded conditions.