Probabilistic Advancing Cross-Diagnosis for Bridge Structures by Using Coherent Laser Radar

Global diagnosis for bridges involves identifying the existence of deterioration or damage, as well as its location or vicinity. This research project develops a new technique for global diagnosis—the probabilistic advancing cross-diagnosis (PAC) method—by using a recently developed coherent laser radar system (CLRS). The PAC method takes advantage of CLRS’s efficient deformation-data acquisition by scanning a large area and then processing the data to perform probability-based cross-diagnosis. This method was applied in the structures lab at Wayne State University to a model structure, with the cooperation of FHWA’s Turner-Fairbank Highway Research Center. Several damage scenarios were simulated by increasing and reducing stiffness of the test beam in the model structure. Results show that the proposed PAC method is promising and should be tested in the field.