Title: Analysis of Concrete Deep Beams with Fibre-Reinforced Polymer (FRP) Bars by Indeterminate Strut-and-Tie (IST) Method

Author(s): Shuqing Liu and Maria Anna Polak

Publication: Symposium Paper

Volume: 360

Issue:

Appears on pages(s): 759-770

Keywords: Structural Concrete, Strut-and-Tie Method, Deep Beams, Fibre-Reinforced-Polymer (FRP) bars

DOI: 10.14359/51740661

Date: 3/1/2024

Abstract:
This paper presents an indeterminate strut-and-tie (IST) method to analyze concrete deep members reinforced with fibre-reinforced polymer (FRP) bars. Because FRP bars are linear-elastic and brittle at failure, the classical ST method based on steel yielding cannot be used to analyze FRP-reinforced concrete deep beams, and current code provisions lack guidance on such designs. Thus, the IST method is proposed for the analysis. This work addresses the details of using the proposed IST method to analyze FRP-reinforced concrete deep beams, including how to size the struts and nodes without assuming steel yielding, how to model the compressive behaviour of concrete struts reasonably, and how to construct and analyze statically indeterminate ST models. Six FRP-reinforced concrete deep beams with stirrups and six beams without stirrups are analyzed in this work, and it is found that the proposed method works well to predict the shear strength of FRP-reinforced concrete deep beams by comparing the analytical results with the test results.