Investigations on the Shear Behavior of Bridge Girders Made of Normal and Ultra-High Performance Fiber-Reinforced Concrete

To further analyze the shear behavior of continuous prestressed bridges, two research projects are currently being examined at the Chair of Concrete and Masonry Structures of the Technical University of Munich (TUM). While one project focuses on the actual bearing capacity of older existing bridges, the other one deals with the development of prefabricated prestressed ultra-high performance fiber-reinforced concrete (UHPFRC) I-beams utilizing different reinforcing concepts and materials. Alongside complex numerical investigations, a comprehensive experimental test series will be carried out. For all tests an innovative experimental setup is being developed, which allows full scale testing of concrete beams at reduced length using the substructure technique. On the one hand the shear resistance of slender prestressed UHPFRC bridge girders with very thin webs is investigated. For these I-shaped beams the shear behavior for different types of shear reinforcement, as well as the size effect for different cross-section heights is investigated. Furthermore, the influence of various types of shear reinforcement, especially outdated stirrups no longer permitted by current standards, on the shear capacity of existing bridges is being researched. In detail these stirrups, which can often be found in older bridges, are not closed or have insufficient overlap length. As the shear design is a major issue for the re-analyses of bridges in Germany where the provided stirrups do not meet current requirements, the impact of the stirrup geometry on the shear capacity of bridge girders made of normal strength concrete has to be investigated. The paper generally explains the above mentioned research projects and presents the results of preliminary investigations.

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  • English

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  • Accession Number: 01613425
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Aug 29 2016 8:48AM