Title:
Investigation of Corbels Designed According to Strut-and-Tie and Empirical Methods
Author(s):
Heather R. Wilson, Hossein Yousefpour, Michael D. Brown, and Oguzhan Bayrak
Publication:
Structural Journal
Volume:
115
Issue:
3
Appears on pages(s):
813-824
Keywords:
code provisions; corbel; diagonal cracking; secondary reinforcement; shear strength; strut-and-tie
DOI:
10.14359/51701282
Date:
5/1/2018
Abstract:
Corbels are short, typically shear-controlled cantilevers that transfer loads to columns. Currently, ACI 318-14 provisions allow the structural design of shear-controlled corbels through either an empirical design method or the strut-and-tie method (STM). The objective of this paper is to evaluate STM as an independent design method for corbels and investigate the differences stemming from the use of STM compared with the empirical design method. Four full-scale double-corbel specimens were designed, fabricated, and tested at Ferguson Structural Engineering Laboratory. Two specimens were designed using the empirical method and two specimens were designed using STM, with and without crack-control reinforcement. Measured load-carrying capacities exceeded the capacities calculated using STM for all specimens, and no signs of premature failure were observed in the corbel detailed based on the STM. The results of this study suggest that STM can be used for corbels, and the empirical detailing requirements specific to corbels might not be necessary when using STM.
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