Riveted steel deck girders comprise the majority of the deck girders on North American railroads, and they have been in service for many decades. Fatigue cycle accumulation creates concern that crack development might require repair or replacement of these spans. Given the number of spans, examination of individual locations is time-consuming and inefficient. Railroad bridge designs are standardized and the use of standard spans means a fatigue check also can be standardized. A method is presented that takes advantage of design parameters of girders for a range of span lengths designed to a specific loading to check for potential fatigue cycle accumulation. Advantages of the method are that multiple span lengths are checked for loadings from actual equipment instead of an assumed loading. Another major advantage is the ability to determine whether fatigue cycles are accumulating at the rate of one cycle per railcar or one cycle for an entire train. The method allows a quick assessment of a typical group of spans designed to a standard, pinpointing areas for more detailed analysis. An assessment of past and present railcar equipment is presented compared to standardized AREA/AREMA girder designs. The analysis explains girder performance trends that have been noted over the years. In particular, longer spans generally have not shown fatigue-related problems. The analysis also indicates that a significant portion of the railway deck girder inventory, especially the longer spans, are not likely to show fatigue-related problems for many more decades under typical traffic conditions.
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