New Connection Details for Concrete Filled Tubes to Precast Concrete Elements for Accelerated Bridge Construction Applications

Authors

FNU SHEHARYAR E REHMAT, Florida International UniversityFollow

Document Type

Dissertation

Degree

Doctor of Philosophy (PhD)

Major/Program

Civil Engineering

First Advisor's Name

Atorod Azizinamini

First Advisor's Committee Title

Committee chair

Second Advisor's Name

Arindam Gan Chowdhury

Second Advisor's Committee Title

Committee member

Third Advisor's Name

Armin Mehrabi

Third Advisor's Committee Title

Committee member

Fourth Advisor's Name

Kingsley Lau

Fourth Advisor's Committee Title

Committee member

Fifth Advisor's Name

Wallied Orabi

Fifth Advisor's Committee Title

Committee member

Keywords

Seismic connections, Accelerated Bridge Construction, Structural Engineering

Date of Defense

6-23-2022

Abstract

The synergistic interaction of steel and concrete in concrete filled tube (CFT) composite members improves structural performance by delaying local buckling of steel tube. Compared to localized confinement provided by discreet ties in reinforced columns, the steel tube provides continuous confinement to infill concrete which results in improved energy dissipation and ductility performance. Concrete filled tubes (CFTs) provide improved structural strength and ductility while minimizing the cost of column formwork. The construction sequence of CFT allows its use for accelerated bridge construction applications. The use of CFTs for bridges in the U.S. has been limited mainly due to lack of design provisions, particularly for seismic zones. This research proposes a new detail for column-to-footing connection using ultra-high performance concrete (UHPC). Several details were studied, and a detail comprises of CFT embedded in a layer of UHPC located near the plastic hinge zone of the column is selected to for experimental and numerical study. Using experiments from existing literature, pretest finite element analysis was carried out on the design parameters including effect of confinement, tension pull out and shear behavior of the connectors.

Three connection details were experimentally studied under a combination of constant axial and incremental lateral cyclic load. The proposed connection is desired to have a ductile behavior with the plastic hinge forming away from the footing which is typically designed as a capacity protected element. The results of the experiments and pretest analysis were used to carry out parametric finite element analysis. Further experimental and numerical study is proposed to recommend design and construction provisions.

Identifier

FIDC010759

ORCID

0000-0003-2907-3521

Previously Published In

• Rehmat, S., Sadeghnejad, A., Mantawy, I.M. and Azizinamini, A., 2021. Experimental study on concrete filled steel tubes to footing connection using ultra-high performance concrete. Engineering Structures, 242, p.112540.
• Azizinamini, A., Rehmat, S. and Sadeghnejad, A., 2019. Enhancing resiliency and delivery of bridge elements using ultra-high performance concrete as formwork. Transportation Research Record, 2673(5), pp.443-453.

Recommended Citation

SHEHARYAR E REHMAT, FNU, "New Connection Details for Concrete Filled Tubes to Precast Concrete Elements for Accelerated Bridge Construction Applications" (2022). FIU Electronic Theses and Dissertations. 5038.
https://digitalcommons.fiu.edu/etd/5038