Alternative Connections for Accelerated Construction of Simple for Dead load and Continuous for Live load Steel Bridge System

Authors

Amir Sadeghnejad, 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

Ton-Lo Wang

Second Advisor's Committee Title

committee member

Third Advisor's Name

Armin Mehrabi

Third Advisor's Committee Title

committee member

Fourth Advisor's Name

Seung Jae Lee

Fourth Advisor's Committee Title

committee member

Fifth Advisor's Name

Wallied Orabi

Fifth Advisor's Committee Title

committee member

Keywords

Bridge Engineering, Steel Bridges, Seismic Design, Continuity detail, Simple for Dead load and Continuous for Live load, Ultra-high Performace Concrete

Date of Defense

3-26-2021

Abstract

The simple for dead load and continuous for live load (SDCL) steel bridge system has been implemented in non-seismic areas with desirable field performance. However, in seismic areas, the application of the SDCL steel bridge system has not been implemented due to a lack of verified seismic details. A connection for the steel girders over an intermediate pier using a concrete diaphragm suitable for seismic areas was developed using numerical analysis. The field application of the developed connection required experimental verification and validation.

One of the main objectives of this study was experimental verification of the developed detail under seismic loads. In this study, component level and system-level testing were performed on scale models of SDCL steel bridge system made with the developed connection detail. Component testing was performed on a scaled connection detail under cyclic loads. And the shake-table test was done on a scaled two-span steel bridge, which was subjected to earthquake excitations. In both tests, the behavior of the connection detail was desirable. The plastic hinge was formed at predefined locations and prevented the capacity-protected elements from damage. Based on the result of the experiments and complementary numerical analysis on a full-scale prototype bridge a set of design recommendations was developed.

Another objective of the study was the development of a simplified connection detail utilizing ultra-high performance concrete (UHPC). UHPC has superior mechanical properties such as high compressive and tensile strength and high ductility. UHPC is an attractive material for accelerated bridge construction applications because of its high early strength gain. In this study, a new connection detail utilizing UHPC was developed using numerical analysis. The numerical models were validated with the available experimental data. Multiple sets of parametric studies were performed to develop the connection detail and understand the behavior of the connection under various loading scenarios. The result of the numerical analysis was used to develop a set of design recommendations for the UHPC connection of the SDCL steel bridge system in non-seismic and seismic areas.

Identifier

FIDC009695

ORCID

0000-0001-5172-9393

Recommended Citation

Sadeghnejad, Amir, "Alternative Connections for Accelerated Construction of Simple for Dead load and Continuous for Live load Steel Bridge System" (2021). FIU Electronic Theses and Dissertations. 4636.
https://digitalcommons.fiu.edu/etd/4636