Title:
Testing and Strut-and-Tie Modelling of Beams with GFRP Reinforcements
Author(s):
Martin Krall and Maria Anna Polak
Publication:
Symposium Paper
Volume:
322
Issue:
Appears on pages(s):
11.1-11.12
Keywords:
Deep Beam; FRP; GFRP; Indeterminate Strut-and-Tie; IST Method; Shear; Shear-Compression; Stirrups; Strut-and-Tie
DOI:
10.14359/51706962
Date:
6/18/2018
Abstract:
This paper presents the results of tests done on concrete beams reinforced with glass fibre reinforced polymer (GFRP) longitudinal bars and GFRP stirrups. The main test variables were the size, the amount, and the arrangement of longitudinal reinforcement as well as the size and spacing of closed loop stirrups. Six beams are divided into two series defined by stirrup spacing, or three pairs defined by longitudinal bar arrangement. The results indicate that the specimens with no stirrups failed in shear-tension while the beams with stirrups failed in shear-compression showing deep beam behaviour. The results were compared to predictions from several methods, namely a novel Indeterminate Strut-and-Tie (IST) method formulated specifically for use with brittle reinforcements, as well as the shear models of the ACI 440.1R-06 guidelines, the CSA S806-12 standard, and the Nehdi et al. (2007) method. The IST method produced the best predictions followed by the method of Nehdi et al. as both are formulated for use with deep beams.
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