Abstract

Government reports and published research have flagged and brought to public attention the deteriorating condition of a large percentage of bridges in Canada and the United States. Inspection and rehabilitation programs are being implemented to monitor and maintain deteriorated bridge infrastructure. Current practices of bridge inspection and condition assessment rely heavily on visual inspection, limited basic testing such as hammer sounding and chain dragging, and the use of Non-Destructive Testing on ad-hoc basis. These methods suffer from several limitations including subjectivity and uncertainty of visual inspection process, as well as traffic disruption resulting from lane closure during inspection. This research aimed to study, evaluate, and experiment with the use of remote sensing technologies in bridge inspection to minimize drawbacks of current practice. To achieve this objective, two models are developed in this research. The first is a comparative study of remote sensing technologies for concrete bridge condition assessment that provides a systematic approach of selecting most suitable technologies for use in condition assessment. Seven remote sensing technologies are examined in this model. It recommends technologies to be implemented based on a set of flexible multi-attributed criteria. The model provides flexibility to select specific set of these criteria and to define their weights based on user preferences and project objectives. The second model proposes a hybrid system of remote sensing technologies to augment current practice in bridge inspection and eliminate some limitations such as minimizing traffic disruption while performing bridge inspection and enhancing inspection data analysis and visualization. The hybrid system integrates the use of thermal Infrared (IR) and Ground Penetrating Radar (GPR). These technologies have the ability of acquiring data from a distance which minimizes traffic disruption. Results obtained from IR and GPR are in the form of maps of the detected defects on the concrete bridge deck. These maps are used as input in ArcGIS for better representation, visualization, and reporting of the defects and their extents. The hybrid system was examined in a case study of a concrete bridge deck in the city of Laval, Montreal, Quebec, Canada. The results are compared to those obtained using hammer sound test for validation.