Palacios, Guillermo

Seismic Performance of a Highly Damage-Tolerant Ultra-High Performance Fiber-Reinforced Concrete (Uhp-Frc) Column

Abstract eng:
Reinforced concrete (RC) columns in the lower stories of high-rise buildings are usually subjected to high axial loads and large lateral earthquake forces in seismic regions. In addition, to satisfy the strength limit state, these RC columns have to exhibit adequate ductile behavior without dramatic strength loss. The application of high-strength concrete (HSC) for the design of such columns could be attractive by potentially reducing the stress demands. However, the increased brittleness of HSC makes it less favorable for the seismic design of structures. In this study, the potential application of ultra-highperformance fiber-reinforced concrete (UHP-FRC) to improve the seismic performance of RC columns was evaluated based on its capability to enhance both the strength and ductility of conventional concrete materials. As an innovative material, UHP-FRC provides high compressive strength (150~207 MPa), excellent tensile cracking behavior, and improved compressive ductility with excellent confinement characteristics. The addition of high strength steel microfibers into the concrete mix can alleviate the need for excessive transverse reinforcement. In this study, full-scale moment-frame columns, constructed with both normal strength concrete and UHP-FRC, were tested under cyclic displacement reversals up to collapse. The performance of the UHP-FRC column is evaluated by comparing it with the conventional RC column. Test results show that the UHP-FRC column exhibited a completely different failure mode from the conventional RC column by improving the confinement effect and avoiding concrete crushing. Experimental results show that the UHP-FRC column exhibited a higher peak strength and greater drift capacity. The lateral displacement of the ACI compliant RC column primarily resulted from the flexural rotation of the plastic hinge region above the column base; on the other hand, the lateral displacement of the UHP-FRC column came from the plastic rotation at the column base due to a strain penetration effect into the footing.

Contributors:

Chao, Shih-Ho

Conference Title:

Proceedings of the 16th World Conference on Earthquake Engineering

Conference Title:

16th World Conference on Earthquake Engineering

Conference Venue:

Santiago (CL)

Conference Dates:

2017-01-09 / 2017-01-13

Rights:

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