Integrated remote sensing and visualization (IRSV) system for transportation infrastructure operations and management, phase two, volume 3 : advanced consideration in LiDAR technology for bridge evaluation.

PDFTech ReportUSDOT/RITA DT0S59-07-H-005DT0S59-09-H-0007Bridge management systemsRemote sensingInspectionCondition surveysLaser radarStructural analysisVisualizationStructural health monitoringAlgorithmsUnited StatesUniversity of North Carolina at Charlotte. Transportation Policy StudiesChen, Shen-EnBian, HaitaoBai, LibinHauser, EddUniversity of North Carolina at Charlotte. Transportation Policy StudiesUnited States. Dept. of Transportation. Research and Innovative Technology AdministrationUS Transportation CollectionThis report describes Phase Two enhancement of terrestrial LiDAR scanning for bridge damageevaluation that was initially developed in Phase One. Considering the spatial and reflectivityinformation contained in LiDAR scans, two detection algorithms were developed to documentthe extent of bridge surface damage. The first algorithm introduced in this report is based onspatial information. This algorithm can detect various damages on a bridge structure according tothe extent of surface damage. Because some damage may involve deep area losses that are notalong the laser line-of-sight (LOS), an experiment is conducted to find out the best location to setup a LiDAR. The two damage detection algorithms are presented and compared with scans onactual bridge damages to evaluate their effectiveness.A further study estimated the potential of including reflectivity data to improve defect detection.The addition of reflectivity in damage diagnostics was determined to be useful for defectdetection of curved surfaces. The study shows that the reflectivity of LiDAR scan could be usedto support the automatic defect detection in bridge inspection by combining it with the currentposition-based algorithms.A total of 88 bridges were studied during the two-year project period. Bridge scan data wereanalyzed using a spatial-based damage detection algorithm, which shows that the LiDARapplication is a useful supplement to traditional visual inspection. Possible improvements in thefuture research could be achieved by optimizing existing algorithms