Time-dependent reliability analyses of prestressed concrete girders strengthened with CFRP laminates

Fernandes, P.; Dias-da-Costa, D.; Hadigheh, S.A.; Neves, L.A.C.; Gomes, S.

Abstract

This paper presents a time-dependent reliability analysis of prestressed concrete girders subjected to degradation caused by pitting corrosion. The procedure presented includes the effects of both spatial and temporal pitting corrosions on prestressing steel, as well as the degradation of the strengthening CFRP laminate used for the rehabilitation of the member. Results indicate that the correlation of corrosion in different segments of the prestressing tendons impacts on the computed safety index for the deteriorated structure. Ditlevsen bounds are proposed for a better approximation of the correlation between failure modes in the spatial discretisation. Results show that such approach produces adequate estimates of the reliability index over the full range of analysis in comparison with other tested models. It is also observed that the degradation of the CFRP laminates does not affect the reliability as significantly as corrosion, and that traffic loads, models uncertainties, corrosion error and corrosion rate are the most relevant variables in the analysis, followed by prestressing strength and concrete cover. The significance of the variables changes with time: the corrosion rate, corrosion model error and concrete cover increase in importance with the development of corrosion, whereas traffic loads become gradually less important.

Citation

Fernandes, P., Dias-da-Costa, D., Hadigheh, S., Neves, L., & Gomes, S. (2019). Time-dependent reliability analyses of prestressed concrete girders strengthened with CFRP laminates. Engineering Structures, 196, 109297. https://doi.org/10.1016/j.engstruct.2019.109297

• Journal Article Type: Article
• Acceptance Date: Jun 11, 2019
• Online Publication Date: Jun 19, 2019
• Publication Date: Jun 19, 2019
• Deposit Date: Feb 28, 2020
• Publicly Available Date: Jun 20, 2021
• Journal: Engineering Structures
• Print ISSN: 0141-0296
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 196
• Pages: 109297
• DOI: https://doi.org/10.1016/j.engstruct.2019.109297
• Public URL: https://nottingham-repository.worktribe.com/output/4049828
• Additional Information: This article is maintained by: Elsevier; Article Title: Time-dependent reliability analyses of prestressed concrete girders strengthened with CFRP laminates; Journal Title: Engineering Structures; CrossRef DOI link to publisher maintained version: https://doi.org/10.1016/j.engstruct.2019.109297; Content Type: article; Copyright: © 2019 Elsevier Ltd. All rights reserved.