Title:
Aggregate Size on Punching Shear Behavior of Interior Slab-Column Connections
Author(s):
Marnie B. Giduquio, Min-Yuan Cheng, and Shang-Wei Lin
Publication:
Structural Journal
Volume:
120
Issue:
6
Appears on pages(s):
113-122
Keywords:
aggregate size; flexural reinforcement; punching shear
DOI:
10.14359/51739091
Date:
11/1/2023
Abstract:
Coarse aggregate size has been considered as one of the critical
parameters affecting the shear resistance of reinforced concrete
elements. However, existing research discussing its effects on
punching shear is limited. In this study, 12 large-scale interior
slab-column subassemblages were tested to investigate the influence
of coarse aggregate size on the punching shear behavior
of interior slab-column connections subjected to monotonically
increased concentric load. Three aggregate sizes were selected:
one with a nominal maximum coarse aggregate size, dagg, of 3/16 in.
(4.75 mm), another with dagg of 3/4 in. (19 mm), and the last with
dagg of 1 in. (25 mm). The experimental evidence indicated that all
specimens failed in punching shear. In general, the increase in dagg
improved the punching shear response, with an increase in either
the normalized maximum shear or the corresponding deformation,
or both. The effects of the dagg were more consistent and apparent
in specimens with slab tensile flexural reinforcement ratios of 0.80
and 1.28%, where both the normalized maximum shear and the
corresponding deformation increased as the dagg increased. For the
specimens with (low) slab tensile flexural reinforcement ratios of
0.40 and 0.53%, the increase in coarse aggregate size led to an
increase in the normalized maximum shear and the corresponding
deformation when the dagg was increased from 3/16 to 3/4 in. (4.75
to 19 mm) due to better bond strength. As the dagg was further
increased from 3/4 to 1 in. (19 to 25.4 mm), the effects of the dagg on
the normalized maximum shear and the corresponding deformation
were not apparent in the specimens with slab tensile reinforcement
ratios of 0.40 and 0.53%.