13. US 83 Over the White River

Donated by: South Dakota Department of Transportation (SD DOT)
Original Location:  US 83 Over the White River; Jones and Mellette Counties
Year Built: 1956
Emergency Repair:  1999
Fracture discovered: August 1999
Donated to SBRITE:  May 2022

Structure Type: Welded multi-girder continuous span steel bridge
Total Bridge Length:  432 ft (fracture span 120 ft)
Deck Width:  32 ft-4 in. out to out
Number of Spans: 4

The girder is a 5’-2” welded plate girder. There were four girder lines and span which the fracture occurred was 120 ft.  However, the overall length of the continuous girders was 432 ft.  The fracture appeared to have initiated  at a top flange welded splice where the flange section changed in both width and thickness. The detail used to make this transition was in incredibly poor detail where a beveled and tapering (in width) plate was but welded in (see photos). The fracture was found during our normal inspection on cycle.  There was no distress observed in the remaining girders of this four-girder cross section.   The girder was repaired with a bolted splice and carried traffic for years following the discovery of the fracture.  The bridge has since been replaced.