Three Dimensional Micro Detection Scheme of Fatigue Cracks in Steel Box Girder with HIROX Testing System

In practical steel box girder, the fatigue cracks are inevitably existed in steel bridges after they are burdened with the overloading vehicles and larger numbers of automobiles. How to efficiently detect the fatigue cracks, especially the initial fatigue cracks, become one of the most important question to be solved for the steel box girder. HIROX testing system is based on three dimensional micro detection technique, which was successfully used into the domains of aeronautics and astronautics. Three dimensional micro detection scheme of fatigue cracks in steel box girder with HIROX testing system is studied in this paper. Through the data from the testing design, the important characteristic width and length of the fatigue crack can be achieved, which can be used for the grasping of the mechanism of the steel box girder.