Development of an experimental system for fatigue-cracking from weld roots between deck plate and u-rib in orthotropic steel decks

Fatigue cracks have recently been observed at weld joints connecting deck plate and U-rib in an orthotropic steel deck. Some of the cracks initiate from the weld roots and then propagate through the thickness of the deck plate. If the deck plate are left unattended after fatigue-cracking, traffic accidents may be caused by partial sinking of the deck plate. In addition, considerable corrsion damage may also occur in the U-rib due to rainwater penetrating through the fatigue-cracked deck plate. The purpose of this research is to develop an experimental system for fatigue-cracking from the weld root in order to investigate the mechanisum of fatigue-cracking, the retrofitting methods, etc. Static and fatigue tests were carried out on model specimens of the orthotropic steel deck focusing on the scatter effect of traffic wheel loadings by asphalt pavement and on the service stress wave.