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Ultra-high-performance concrete (UHPC) and other high-performance fiber reinforced cementitious composites (HPFRCC) have shown promising results for use in seismic resistant flexural dominant structural members in terms of strength, deformation capacity, and energy dissipation capacity. Different studies investigating the flexural behavior of structural elements using these materials have found behaviors such as an increase in deformation capacity with increasing reinforcement ratio and failure of member due to reinforcing bar fracture, which directly contrast the behavior seen in conventional reinforced concrete structures. However, only a limited number of systematic studies have been conducted for members subject to axial and flexural loading. Hence, a study aiming to investigate the influence of reinforcement ratio and axial load on the behavior of column members subject to axial and lateral loads was designed. Eight specimens with variations in HPFRCC material, reinforcement ratio, and axial load ratio were subjected to axial and reversed cyclic lateral loads for experimental testing. The influence of the selected parameters on results such as load-displacement response, damage patterns, longitudinal reinforcement strain profiles, and failure mechanisms are discussed.
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Experimental Characterization of Plastic Hinge Behavior from Flexure and Axial Effects
The unique mechanical properties of ultra-high performance concrete (UHPC) causes changes in failure modes and ductility in reinforced components. Numerous experiments have shown these materials, and others with similar ductile characteristics in tension, can improve the damage tolerance, strength, and ductility of members subjected to large deformations from seismic loading and similar extreme conditions. The use of these materials, however, has not been systematically studied to understand their application at a system-level performance and design procedures have been complicated due to their unconventional failure mechanism. This project aims to fill this gap by testing a targeted set of components subjected to combined effects of axial loads and bending with variations in axial load ratio and longitudinal reinforcement ratio. Additional experiments are planned to compare performance across other ductile concrete materials with variations in mechanical properties. The experimental results including load-deformation, reinforcement strain, concrete surface strain will be used to understand the parameters that have the highest influence on plastic hinge length and moment-rotation response which can ultimately help to validate analytical models against experiments based on these key parameters.
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- Award ID(s):
- 2141955
- PAR ID:
- 10432446
- Editor(s):
- Aaleti, Sriram; Okumus, Pinar
- Date Published:
- Journal Name:
- International Interactive Symposium on UHPC
- Volume:
- 3
- Issue:
- 1
- Page Range / eLocation ID:
- 77
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Conference Paper:
- https://doi.org/10.21838/uhpc.16690
