Evaluation for Punching Shear Strength of Slab-Column Connections with Ultra High Performance Fiber-Reinforced Concrete Overlay
This paper presents the test results on 5 slab-column connection specimens with Ultra High Performance Fiber-Reinforced Concrete (UHPFRC) overlay including 1 control specimen to investigate retrofitting effect of UHPFRC overlay on the punching shear capacity. The test parameters were the thickness of the UHPFRC overlay and the amount of steel re-bars in it. All specimens failed in punching shear mode with abrupt failure aspect. The test results showed that by adding a thin layer of UHPFRC over the Reinforced Concrete (RC) substrates, considerable increases in global punching shear resistance up to 82% and structural rigidity were achieved. Furthermore, based on the cracking patterns the composite systems appeared to be governed by two failure modes: 1) diagonal shear failure in RC section and 2) debonding failure at the interface.
 ACI Committee 318. (2011). Building Code Requirements for Structural Concrete (ACI 318-11) and Commentary (pp. 503). Farmington Hill, MI: American Concrete Institute.
 Bastien-Masse, M., and Brühwiler, E. (2016). Experimental investigation on punching resistance of R-UHPFRC-RC composite slabs. Materials and Structures, 49(5), 1573-1590.
 British Standards Institution. (2004). Eurocode 2: Design of Concrete Structures – Part 1-1: General Rules and Rules for Building (pp. 225). Bruxelles, Belgium: European Standard EN-1992-1-1: 2004:E, European Committee for Standardization.
 Japan Society of Civil Engineers. (2010). Standard Specifications for Concrete Structures-2007 ‘Design’ (pp. 469). Tokyo, Japan: Japan Society of Civil Engineers.
 Kinnunen, S., and Nylander, H. (1960). Punching of concrete slabs without shear reinforcement (p.112). Elander
 Korea Concrete Institute. (2012). Korean Structural Design Code (KCI 2012) (pp. 342). Seoul, Korea. (in Korean).
 Muttoni, A. (2008). Punching shear strength of reinforced concrete slabs without transverse reinforcement. ACI structural Journal, 105(EPFL- ARTICLE-116123), 440-450.
 Muttoni, A., and Schwartz, J. (1991). Behavior of beams and punching in slabs without shear reinforcement. In IABSE colloquium (Vol. 62, No. EPFL-CONF-111612, pp. 703-708). IABSE Colloquium.
 Noshiravani, T., and Brühwiler, E. (2013). Experimental investigation on reinforced ultra-high performance fiber-reinforced concrete composite beams subjected to combined bending and shear. ACI Structural Journal, 110(2), 251.
 Wuest, J (2007) Comportement structural des bétons de fibres ultra performants en traction dans des éléments composes (Doctoral dissertation, Ecole Polytechnique Fédérale de Lausanne). (in French)