Intelligent feature extraction, data fusion and detection of concrete bridge cracks: current development and challenges

As a common appearance defect of concrete bridges, cracks are important indices for bridge structure health assessment. Although there has been much research on crack identification, the evolution mechanism is still far from practical applications. In this paper, state-of-the-art intelligent theories and methodologies feature extraction, data fusion detection based data-driven approaches comprehensively reviewed. The discussed three aspects: extraction level multimodal parameters cracks, description diagnosis damage states. We focus previous concerning quantitative characterization problems their implementation in while highlighting some major drawbacks. addition, current challenges potential future directions discussed.