Influence of Fatigue Crack on Strains State Within Assembly Holes in a Web of Steel Bridge Girder

The paper presented an attempt to assess service life of steel girders in military bridges (or bypass temporary bridges) when fatigue cracks are detected in them. a function describing the geometry of fatigue cracks,the so-called crack shape factor y,for two different,assumed calculated models,was presented. the function was used to plot sample graphs allowing assessing the remaining service life of such structural elements or engineering structures in a simple way. this method of analyzing can be used not only for the military bridges but also for other steel structures with existing cracks. the work also presented assessments of possible applications of two fem calculated models using shell elements to test stress and deformation at the top part of a fatigue crack located in a web of a steel girder used in the military bridges. the results of the conducted numerical analyses were compared with the results obtained in experimental research conducted in laboratory conditions using extensometers. © 2017,iran university of science and technology.