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Title |
Punching Shear Strength of Deck Slabs Made of Ultra High Performance Concrete
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Authors |
조창빈 ; 김병석 ; 황훈희 ; 최경규 ; 최석환 |
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Keywords |
콘크리트 바닥판 슬래브 ; 뚫림전단 ; 초고성능콘크리트 Concrete deck slab ; Punching shear ; Ultra high performance concrete |
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Abstract |
Thinner and lighter structural members can be designed by utilizing the high stiffness and toughness, and high compressive strength of UHPC(ultra high performance concrete), which reaches up to 200MPa. The punching shear capacity of UHPC was investigated in this paper aiming for the application of UHPC to bridge decks. Six square slabs were fabricated and punching shear test was performed under fixed boundary condition. Different thicknesses of test slabs, which were 40mm and 70mm, were selected. The shape ratio of loading plates were ranged between 1.0~2.5. 40mm thickness slabs showed longer softening region after the peak load and, on the other hand, 70mm thickness slabs revealed a more brittle shear failure. Experimental results were analyzed using various existing punching shear predicting equations. Ductalⓡ equation and JSCE equation better predicted for 40mm slabs, and Harajli et al. equation and ACI-Ductalⓡ equation better suited for 70mm slabs. Nevertheless generally they didn't well predict the test results. A new punching shear equation which was derived based on the actual failure mechanism was proposed. The proposed equation appeared to better predict the punching shear strength of UHPC than other available equations.
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