State of Art Image-Based Inspection Methods Used on Japanese Expressways

The tunnel and bridge assets on the Japanese expressways constitute a very large sum of investment. These tunnes and bridges deteriorate quickly due to various factors such as aging,environmental exposure, and mechanical effects. The cracking of pavements constitutes serious maintenance item. Proper inspection and investigation are essential to evaluate the condition of structures and efficient non-destructive test methods are important for improved asset management. This paper presents a pavement crack investigation technology adopted automatic image processing, a damage evaluation technology for steel bridge paint which adopted analysis of digitized photos, and a crack investigation technology on tunnel concrete lining adopted laser measurement equipment which is mounted on high speed vehicles.