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Adequate bonding between rebar and concrete is critical to ensuring the reliable performance of RC structures. It is found empirically that bond behavior is affected by many factors, including concrete cover, transverse reinforcement, rebar geometry, concrete properties, etc. While many past studies have focused on the prediction of bond strength, how those factors influence the bond failure mode is not well investigated. The goal of this research is to develop a bond failure mode prediction model considering corrosion. The model development is based on bond testing results of 44 beam-end specimens with various rebar size, corrosion levels, covers, and stirrup confinement. This study adopts logistic and lasso logistic regression, where the failure mode is the categorical dependent variable and the aforementioned factors that could influence the bond behavior are the independent variables. The developed model can be can be further used for corroded RC structure performance evaluation.
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Probabilistic prediction model for RC bond failure mode
Adequate rebar-concrete bonding is crucial to ensure the reliable performance of reinforced concrete (RC) structures. Many factors such as the concrete properties, concrete cover depth, transverse reinforcement, and the presence of corrosion will affect the bond behavior, and consequently, the structural performance. While many prior studies have focused on the influence of the aforementioned factors on the bond strength, the impact of these factors on the bond failure mode has not been thoroughly investigated. A probabilistic bond failure mode prediction model that considers various influencing factors including loading type and corrosion is developed in this study. This study uses the bond testing results of 132 beam-end specimens subjected to monotonic and cyclic loading and adopts classification methods to develop the prediction model, which is then used to evaluate the impact of bond behavior on the reliability of a RC beam with a lap splice.
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- Award ID(s):
- 1635507
- PAR ID:
- 10301590
- Date Published:
- Journal Name:
- Engineering structures
- Volume:
- 233
- ISSN:
- 0141-0296
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1016/j.engstruct.2021.111944
