International Concrete Abstracts Portal

Title: Strengthening of a Bridge Using Post-Tensioned Near‑Surface-Mounted Carbon Fiber-Reinforced Polymer in Multi-Hazard Environment

Author(s): Yail J. Kim, Jae-Yoon Kang, Jong-Sup Park, and Woo-Tai Jung

Publication: Structural Journal

Volume: 115

Issue: 2

Appears on pages(s): 451-462

Keywords: bridge; carbon fiber-reinforced polymer (CFRP); deterioration; multi-hazard; near-surface-mounted (NSM); post-tensioning; strengthening

Date: 3/1/2018

Abstract:
This paper presents an analytical investigation into the performance of a reinforced concrete bridge girder strengthened with post-tensioned near-surface-mounted (NSM) carbon fiberreinforced polymer (CFRP) strips in a corrosion-overload multihazard environment. Stochastic models are formulated to examine the service- and strength-level responses, functional requirements such as deformability and vulnerability, and time-dependent reliability of the strengthened girder. In conjunction with environmental data recorded for 30 years, four service zones specified in the American Association of State Highway and Transportation Officials (AASHTO) Load and Resistance Factor Design (LRFD) Bridge Design Specifications are employed to generate practical research outcomes. Chloride-induced diffusion becomes more active in summer compared with other seasons. As such, stresses in the girders’ steel reinforcement increase with the progression of corrosion; however, the increase does not cause a fatigue concern. A marginal increase in CFRP stress is noticed, spanning a 100-year service period. The deformability of the strengthened girder is acceptable within a reduction range of up to 20%. The multi-hazard distress augments the vulnerability of the girder and, accordingly, affects the long-term reliability, which should be taken into consideration when implementing the NSM CFRP technology.