Retrofitting of Bridge Elements Subjected to Predominantly Axial Load Using UHPC Shell

Authors

Mahsa FarzadFollow

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

Arindam Gan Chowdhury

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

Sixth Advisor's Name

Kingsley Lau

Sixth Advisor's Committee Title

Committee member

Keywords

Retrofit, Repair, UHPC, Substructure, Concrete, Bridge, Corrosion, Service life

Date of Defense

4-8-2019

Abstract

In the United States, ~30% of the ~600,000 highway bridges are categorized as structurally deficient or functionally obsolete. These bridges should be replaced or upgraded to sustain the transportation needs of the growing public and private sectors of the U.S. economy. It is not uncommon for structures to have advanced levels of corrosion-induced damage where major repair and maintenance works are required. However, the transportation infrastructure may undergo disruption during rehabilitation causing interruption to critical economic public, civil and commercial activities. This mandates the development of new techniques and materials for accelerated rehabilitation and resilience. To address this issue, a repair method has been developed at Florida International University (FIU), using Ultra High-Performance Concrete (UHPC) for members under axial load. This research investigates the mechanical and durability performance of the proposed retrofit method through experimental and numerical studies. The properties of UHPC, such as high compressive and tensile strength, workability, and impermeability make it a suitable choice as a repair material for retrofitting the damaged body of the marine vii piles, and application of UHPC could provide an efficient solution to address the pressing issue of bridge rehabilitation. This research firstly aims to investigate the mechanical performance of UHPC repair for damaged bridge columns. To achieve this goal, an experimental study was designed to evaluate the mechanical performance of the repaired columns under a combination of static axial and cyclic lateral loads (to simulate operational conditions). Moreover, the extent of macrocell development between the dissimilar concrete materials was monitored to identify the possible beneficial properties of UHPC related to corrosion. Conclusions and recommendations for capacity restoration and corrosion protection are made based on the results which can be used in evaluating the suitability of UHPC as a strengthening compound in concrete structures for any given application.

Identifier

FIDC007667

Recommended Citation

Farzad, Mahsa, "Retrofitting of Bridge Elements Subjected to Predominantly Axial Load Using UHPC Shell" (2019). FIU Electronic Theses and Dissertations. 4016.
https://digitalcommons.fiu.edu/etd/4016