Title: Effect of GFRP compression reinforcement on long-term deflections

Author(s): Stephanie L. Walkup, Eric S. Musselman, and Shawn P. Gross

Publication: Symposium Paper

Volume: 327

Issue:

Appears on pages(s): 6.1-6.20

Keywords: compression reinforcement; long-term deflection; FRP reinforced beams; beam deflection; deflection multiplier; GFRP reinforced beams

DOI: 10.14359/51713326

Date: 11/1/2018

Abstract:
The effect of compression reinforcement to reduce long term deflections in GFRP-reinforced concrete beams was evaluated. Nine GFRP-reinforced specimens and three companion steel-reinforced specimens were tested under sustained load for a period of 100 days. Long-term deflection data was used to evaluate the reduction in long-term multiplier for GFRP-reinforced beams and the effects of the compression reinforcement to further reduce the multiplier. Compression reinforcement reduced the long-term multiplier for the GFRP- and steel-reinforced specimens. A new equation is proposed to incorporate the compression reinforcement index, kr, in the long-term deflection multiplier for any type of reinforcement. The experimental results also demonstrate that the ratio of the long-term deflection of a GFRP-reinforced vs. steel-reinforced beam can be determined in a relatively short period of time. Experimental results from the present study show that this ratio is 0.87 for the GFRP-reinforced specimens without compression reinforcement, in lieu of the present 0.6 value used in ACI 440.1R. Keywords: