Title |
Evaluation on Shear Performance of the Dapped Ends of Precast Gerber′s U-Beams
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Keywords |
프리스트레스트; 프리캐스트; 전단; 댑단부; 초기균열; 게르버 보; 직사각형 단면; shear; prestressed; precast; dapped end; initial cracking; gerber′s beam; rectangular section |
Abstract |
The dapped ends of the Gerber's beam were designed by PCI(Prestressed Concrete Institute) and CPCI(Canadian Prestressed Concrete Institute) methods. The depths of nibs with precast and topping concrete, which were halves of the total beam depth, were 77 cm md 18.2 cm, respectably. Shear tests were performed on four full scale beam ends. All specimens designed by PCI and CPCI methods showed crackings at the re-entrant coner of dap before the 32 % of full service design loading, and failed at the load level higher than their design strength but less than their calculated nominal strength. The specimens with increased hanger reinforcement show more effective in development of initial crackings, more ductile in failure with distributed crackings, and failed in higher strength than those of PCI requirement. The tested specimens designed by CPCI method were more ductile in failure than those of the PCI methods.
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