Title:
THE TORONTO SIZE EFFECT SERIES
Author(s):
Evan C. Bentz and Michael P. Collins
Publication:
Symposium Paper
Volume:
328
Issue:
Appears on pages(s):
2.1-2.12
Keywords:
shear, size effect, strain effect, safety, experiments, rho
DOI:
10.14359/51711146
Date:
9/12/2018
Abstract:
Over the past 25 years many experiments on the shear strength of reinforced concrete members without stirrups have been performed at the University of Toronto. These include a recently completed 4000 mm (157.5 inch) deep specimen that is the deepest shear test ever performed to date. These results make it very clear that the size effect in shear is critical to understand if safe shear designs are desired. In addition to the size effect is the concept of a strain effect whereby members with higher longitudinal strains also show lower shear strengths. This paper accumulates the results of many of these shear tests in a single paper so that they can be directly compared to each other. The resulting set of tests are compared to the CSA shear design provisions and this code is shown to model them well. In addition, a simple curve-fit equation is generated which also does a good job modelling the size and strain effect tests, but is shown to be a poor model when extrapolated to other practical situations.
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