ABSTRACT
Orthotropic steel deck bridges are employed in many urban expressways in Japan. Many fatigue cracks, which might be caused by overloading vehicles and long in-service periods, are found in the orthotropic steel deck. Since the cracks affect the safety of traveling vehicles, adequate maintenance should be conducted. The objective of this study was to develop a method of detecting a crack propagating in the deck plate through the change in strain response. In this research, fatigue tests were performed using small specimens that imitated a section of the deck plate and the trough rib of an orthotropic steel deck. The size of the deck plate was 1000 mm in length, 280 mm in width, and 12mm in thickness. The trough rib was 100 mm in length. As a result of the test, strain changes due to fatigue crack propagation on the weld toe at the upper side could be detected by measuring strain changes.
