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Indexed by:会议论文

Date of Publication:2008-01-01

Included Journals:CPCI-S

Page Number:921-929

Key Words:ductility; crack; test; beam; UHTCC

Abstract:Low ductility and wide cracks behaved in concrete material present severe challenges to long term service of concrete structures. This paper provides a new solution to these issues by introducing UHTCC material, which is a kind of new random-oriented short PVA fiber reinforced cementitous composites and exhibits ultra-high toughness of up to 3% ultimate tension strain capacity under uniaxial tensile load accompanying with formation of multiple fine micro-cracks with merely 80 mu m average crack width even at ultimate tension strain time. Using UHTCC to fully replace concrete matrix, two groups of 6 steel reinforced UHTCC beams with different reinforcement ratios were tested in four-point bending loading. For comparison purposes, corresponding ordinary steel reinforced concrete beams were prepared. The results indicate that, compared to ordinary steel reinforced concrete beams, RUHTCC beams not only could delay steel yielding and eventually improve structure flexural capacity and ductility, but also could dramatically reduce crack width down to within 0.1 mm at yielding, leading to significantly enhanced durability.