Improving ground penetrating radar evaluation of corrosion in reinforced concrete bridge decks

点击翻译按钮获取中文摘要

This Discovery grant proposal supports a long term research program at Dalhousie University in Non-Destructive Evaluation (NDE) of civil infrastructure by extending techniques for evaluating Ground Penetrating Radar (GPR) data from exposed surface (unpaved) reinforced concrete decks to the more complicated case of asphalt paved decks. Reinforced concrete bridge decks tend to be one of the most problematic elements to accurately diagnose corrosion damage, particularly when asphalt concrete wearing surfaces are present. The proposed research will extend our fundamental understanding of how GPR signal propagation is affected through multilayered pavement systems (bridge decks) and their various degrees of damage and chloride contamination. Specifically, the research will focus on two areas: modeling and quantifying signal attenuation resulting from the condition and thickness of the asphalt concrete; and, the effect of different chloride concentration profiles within the cover layer on the signal loss threshold used to predict corrosion damage. Successful adaptation of the applicant's current approach for evaluating unpaved reinforced concrete bridge decks to the more common and complex case of deteriorated asphalt-paved decks will greatly improve the accuracy and reliability by which repairs of corrosion-induced damage can be estimated and prioritized on a network level. Modeling and calibrating the phenomena over a broad range of normal and high performance concrete mixtures used in industry today will extend its application to a broader range of materials used in service. The ability to evaluate the condition of the asphalt concrete will also have significant impact in highway pavement systems evaluation. One Ph.D. and two Master of Applied Science students will be trained through the proposed research, developing two consulting engineers who are skilled in GPR investigations of infrastructure and one academic researcher who will continue to advance research in this field. The students will gain a foundation of strong research skills and industrial experience through collaboration with international colleagues, local industry, and research presentations at relevant international conferences.