Rapid Repair of Severely Damaged Reinforced Concrete Columns

This project was awarded by the University of Missouri Research Board as seed funding to carry out the testing and preliminary analysis. Funding requested from NUTC in this proposal is to support the continuation of the analysis and simulation of the repaired columns’ behaviors by the PhD student.

Damage to bridge structures during an earthquake can have devastating social and economic consequences, particularly for bridges located along key routes critical for emergency response and other essential functions. According to ATC 18, damage to important bridges should be repairable within three days. Thus rapid and effective repair methods for varying levels of damage are needed to enable quick opening of these bridges and to minimize impact on the community. The subject of this study is the rapid repair of severely-damaged concrete bridge columns under combined loading effects. The term “rapid” in the context of this study refers to a 3-day time period as defined in the literature. Research in this field is currently limited to the repair of columns with slight to moderate damage levels; thus this research will fill in a critical gap in the literature with respect to the severe damage level. In this study, one-half scale concrete bridge columns that have been tested to failure as part of a separate ongoing study are repaired using externally-bonded carbon fiber reinforced polymer (CFRP) wrap. The repaired columns are then tested under the same loading regime as the original columns, combined action of bending, shear, torsion, and axial effects, and the behavior is compared directly with the original response. Since the current literature contains little information with respect to repair of columns subjected to torsion, the inclusion of torsion in the combined loading is a significant contribution to the state of knowledge, and represents a more comprehensive and realistic loading condition than without. Results will serve as the basis for and add credibility to future proposals on rapid repair of bridge columns, with high potential for collaboration with leading researchers in this field.

Anticipated Benefits

Research in this field is currently limited to the repair of columns with slight to moderate damage levels; thus this research will fill in a critical gap in the literature with respect to the severe damage level. Additionally since the current literature contains little information with respect to repair of columns subjected to torsion, the inclusion of torsion in the combined loading is a significant contribution to the state of knowledge, and represents a more comprehensive and realistic loading condition than without. Results will serve as the basis for and add credibility to future proposals on rapid repair of bridge columns, with high potential for collaboration with leading researchers in this field. One such new collaboration has already been established as a result of this ongoing work.

Milestones

Relationship to other Research/Projects

This research was initially funded by the University of Missouri Research Board (UMRB) as a pilot study.  The results to date have led to collaboration with the University of Nevada, Reno and the University of Houston on a newly-awarded project by Caltrans entitled, “Emergency Repair of Damaged Bridge Columns Using Mechanical Splices.”

Technology Transfer Activities

Results of this study will be disseminated through a presentation (poster) at the NUTC conference at Missouri S&T and at least one technical peer-reviewed journal article.

Transportation Research Board Keywords

bridge superstructures, repair, fiber reinforced polymer