مقاله

The maintenance of old bridges is rapidly increasing, since many of them are reaching their design life. Hence requirements for maintaining life evaluation of existing bridges are overwhelmingly increasing for bridge authorities all over the world. Fatigue phenomenon seems to be a great concern in this regard whereas no theoretical methods can evaluate the remaining life of existing bridges accurately. This paper presents the procedure used for assessment of remaining fatigue life of an aging orthotropic steel deck bridge in Tehran including strain field measurements carried out on critical fatigue details as well as laboratory tests on limited samples, taken from similar details of an identical disassembled bridge. Field measurements have been carried out under normal traffic loading during an 8-day period of time. Laboratory tests are made on samples taken from the most critical fatigue details on a region of high stress fluctuation (mid span) and the same details at a stagnant region (supports location) and compared. Similar results were obtained from both approaches showing the investigated bridges will not experience fatigue failure under the current traffic regime.