Arturo Schultz, Professor, Civil Engineering
The Minnesota Department of Transportation (MnDOT) has a large inventory of steel bridges in the trunk highway system, some of which require increased attention regarding their inspection and maintenance. Cost-effective use of MnDOT financial resources required analysis of this inventory to identify bridges that are at an increased risk of fatigue cracking to ensure that increased attention is given to them. Research results from recent studies on assessing fatigue problems in steel bridges and estimating their remaining life, were used to define criteria for steel bridge evaluation and ranking. Studies included those conducted at the University of Minnesota for MnDOT on 1) assessing distortional fatigue, 2) load rating for increased truck weights, and 3) and other problematic details such as cover plates terminated in tension flanges. Deliverables included the development of a bridge analysis and rating scheme on the basis of these recommendations within the framework of MnDOT bridge maintenance procedures.