Title: Rational Fuzzy Logic Condition Rating Model of Reinforced Concrete Bridge Decks Using Non-destructive Testing and Visual Inspection
Author(s): Tarek Omar and Moncef L. Nehdi
Publication: Symposium Paper
Appears on pages(s): 159-174
Keywords: bridge deck, condition rating, fuzzy logic, ground penetrating radar, infrared thermography, uncertainty, visual inspection
Bridge deck condition rating systems commonly use measurements of obvious defects recorded through visual investigation. Accordingly, the condition of bridge decks is rated linguistically with inherent vagueness in the description of the deck condition. Although several advanced non-destructive testing (NDT) technologies have emerged for inspecting bridge decks, their results have yet to be incorporated in the condition rating process. The present study establishes a unique link between NDT technologies and inspector findings by developing a novel bridge deck condition rating index (BDCI). The proposed procedure captures the integrated results of infrared thermography (IRT) and ground-penetrating radar (GPR), along with visual inspection judgement deployed to evaluate a full-scale aging concrete bridge deck. The information sought to identify the parameters affecting the integration process was gathered from bridge engineers with extensive experience and intuition. The analysis
process utilized the fuzzy set theory, thus overcoming the inherent scientific uncertainties and imprecision in the
measurements of bridge deck subsurface defects by IRT and GPR testing along with surface defects identified through bridge inspector observations. Integrating the proposed BDCI procedure with existing bridge management systems can provide a detailed and reliable appraisal of bridge health, thus helping transportation agencies in optimizing budgets and prioritizing maintenance, repair, and rehabilitation efforts.