Title:
In-Plane Shear Transfer between Thin Concrete Slabs with Concrete Shear Keys and Steel Shear Plate
Author(s):
Tae-Sung Eom, Geonung Yoon, In-Ho Kim, and Hong-Gun Park
Publication:
Structural Journal
Volume:
121
Issue:
6
Appears on pages(s):
7-18
Keywords:
composite concrete; cyclic loading; shear friction; shear transfer; slab
DOI:
10.14359/51742134
Date:
11/1/2024
Abstract:
In the present study, shear-friction tests were conducted under
cyclic loading to investigate in-plane shear transfer across a thin
and long interface between new and existing concrete slabs. For
shear reinforcement across the interface, concrete shear keys and
steel shear plates were used in combination with adhesive anchors
(that is, post-installed reinforcing bars). Test results showed that
the shear behavior of the thin slab interfaces was significantly
affected by the types and details of interface reinforcements. The
concrete shear keys and shear plate effectively restrained relative
slip across the interface during the initial behavior and increased
the peak strength, while the adhesive anchors contributed to the
peak strength and post-peak residual strength. Failure modes
were concrete failure around the concrete shear keys (that is,
local crushing and shearing-off) and in the anchorage zone of the
shear plate (that is, cracking and spalling-off). The nominal shear
strengths of the thin slab interfaces were calculated by summing
the shear-friction strength of adhesive anchors, local crushing
strength around concrete shear keys, and shear yield strength of
shear plates. The predicted strength agreed with the test results.
Based on the results, design considerations of shear transfer across
an interface between thin concrete slabs were discussed.
Related References:
ACI Committee 318, 2019, “Building Code Requirements for Structural Concrete (ACI 318-19) and Commentary (ACI 318R-19) (Reapproved 2022),” American Concrete Institute, Farmington Hills, MI, 624 pp.
Bass, R. A.; Carrasquillo, R. L.; and Jirsa, J. O., 1989, “Shear Transfer across New and Existing Concrete Interfaces,” ACI Structural Journal, V. 86, No. 4, July-Aug., pp. 383-393.
Harries, K. A.; Zeno, G.; and Shahrooz, B., 2012, “Toward an Improved Understanding of Shear-Friction Behavior,” ACI Structural Journal, V. 109, No. 6, Nov.-Dec., pp. 835-844.
Kahn, L. F., and Mitchell, A. D., 2002, “Shear Friction Tests with High-Strength Concrete,” ACI Structural Journal, V. 99, No. 1, Jan.-Feb., pp. 98-103.
Kim, Y. H., and Trejo, D., 2014, “Shear-Transfer Mechanism and Design of Shear Connectors for Full-Depth Precast Deck Panel System,” ACI Structural Journal, V. 111, No. 4, July-Aug., pp. 935-944. doi: 10.14359/51686740
Loov, R. E., and Patnaik, A. K., 1994, “Horizontal Shear Strength of Composite Concrete Beams with a Rough Interface,” PCI Journal, V. 39, No. 1, Jan.-Feb., pp. 48-69. doi: 10.15554/pcij.01011994.48.69
Mattock, A. H., 2001, “Shear Friction and High-Strength Concrete,” ACI Structural Journal, V. 98, No. 1, Jan.-Feb., pp. 50-59.
Waweru, R. N.; Palacios, G.; and Chao, S.-H., 2018, “Strength of Interface Shear Reinforcement with Limited Development Length,” ACI Structural Journal, V. 115, No. 4, July, pp. 983-996. doi: 10.14359/51702061