This report is the first of a two-part, three volume final report presenting the findings of the research work that was undertaken to evaluate the behavior of Indiana highway bridges with diaphragm members welded directly to the web of the primary beams and girders. Fatigue cracks have been observed at several bridges that utilize the welded diaphragm connection. The seriousness of the cracking and the corresponding potential risk on the integrity of the bridge superstructure were assessed. Inspection and repair guidelines for bridges with the welded diaphragm connections were also developed as part of the research effort. This volume presents the results of load tests on two bridge structures with different diaphragm connections. The importance of diaphragm configuration on the stress levels developed at the connection detail is presented. The titles of the three volumes (Report Number in parentheses) are listed below: Part I, Volume 1: Field Evaluation (FHWA/IN/JTRP– 2001/10 – I-1) Part I, Volume 2: Laboratory Fatigue Evaluation (FHWA/IN/JTRP-2001/10-I-2) Part II: Evaluation of Blue River Bridge Fracture (FHWA/IN/JTRP-2001/10-II)

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bridge, connection, diaphragm, welded connection, fatigue, cracking, secondary bending, displacement-induced cracking, load-testing, inspection, retrofit, repair, SPR-2113

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Performing Organization

Joint Transportation Research Program

Publisher Place

West Lafayette, IN

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