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Modelling Repair Techniques for Reinforced Concrete Bridge Barriers using Glass Fibre Reinforced Polymer Bars
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- Author / Creator
- Al-Jaaidi, Abdullah G.
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In an era where bridge deterioration due to corrosion has become evident and a pressing concern for future reinforced concrete bridge construction, glass fibre reinforced polymer (GFRP) reinforcement has emerged as a feasible alternative to steel due to its superior corrosion resistance. Research on reinforcing bridge decks and barriers with GFRP bars is well-established, and design provisions have been incorporated in the latest versions of the Canadian Highway Bridge Design Code (CHBDC). However, the CHBDCdoes not provide specifications on repairing GFRP reinforced concrete (GFRP-RC)bridge barriers in case of damage caused by vehicle impact. The absence of specifications on GFRP-RC barriers is attributed to lack of research on the topic. Therefore, this thesis aims to assess the feasibility and efficiency of three repair techniques on damaged GFRP-RC bridge barriers to provide guidelines on the subject. To fulfil this objective, this research was divided into two parts, an analytical part and an experimental part. The experimental part presented five full-scale, 1.5-m-wide, single-slope Alberta Transportation(AT) Test Level-4 (TL-4) RC bridge barriers (used in moderate to high traffic volume highways) and consists of five 2.4 x 1.5-metre concrete decks reinforced either with steel or GFRP bars, or hybrid reinforcement of steel and GFRP. Two specimens represent reference barriers to justify the replacement of steel reinforcement with GFRP and to evaluate the repair techniques' efficiency. Three barrier specimens were meant to reflect three scenarios of repairing damaged bridge barriers with GFRP using the doweling repair technique. This thesis summarized the procedure of static testing of bridge barriers under a monotonic load simulating vehicle impact, as specified by the CHBDC, and presented the accomplished groundwork to prepare and construct the barrier specimens and test them in the future. The analytical part of this research presented simulations of different repair techniques and simulations of the five proposed specimens, that are to be tested in the future, using VecTor2, a finite-element analysis (FEA) software. The analysis results were studied and compared in terms of barrier wall strength, mode of failure, deflections, and rebar strains to evaluate the performance of GFRP-RC barriers and the efficiency of the proposed repair techniques. Reinforcing single-slope AT TL-4bridge barriers with a GFRP reinforcement ratio equivalent to its steel-reinforced counterpart achieved 70% of the steel counterpart's ultimate load capacity and exceeded the S6:19 strength limit by a ratio of 1.14. Using20M (#6) GFRP bars instead of 15M (#5) GFRP bars could increase the barrier’s restored ultimate load capacity to 92% of its steel counterpart's ultimate load capacity. All repair techniques and scenarios for GFRP reinforced barrier overhangs effectively restored most of the original designs' capacity. Two of the proposed doweling repair techniques for GFRP-RC barriers, namely single-headed GFRP-FRC repair and single-headed GFRP-RC repair, proved to be effective in restoring the barrier ultimate load capacity, and they achieved ultimate load capacities of 101.8% and 96.4%, respectively, of the as-designed barrier strength. Repairing barrier overhangs by doweling regular GFRPreinforcement is also a viable option. In the case of repairing a damaged barrier wall, the restored capacity was 97% of the original, and in the case of repairing damage that extends to the deck slab, full capacity was restored. In addition, a parametric study using VecTor2 was conducted to assess the influence of some parameters (e.g. deck thickness, overhang length, dowelled bar spacing) on the proposed barrier designs and repairs to find optimal design values. The data generated from this parametric study were compared and discussed, and it was concluded that, in general, the proposed designs and repairs were sufficient to resist design loads.
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- Subjects / Keywords
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- Graduation date
- Spring 2021
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- Type of Item
- Thesis
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- Degree
- Master of Science
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- License
- This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.