Experience of the Texas Department of Transportation in Repair of Steel Bridge Fatigue

Abstract

Although steel bridges of the Texas Department of Transportation (DOT) generally exhibit satisfactory fatigue performance, several structures have developed fatigue cracks at various welded attachments because of the previous use of fatigue-prone details. These bridges were typically constructed between the 1950s and 1980s, before the knowledge base of steel bridge fatigue and fracture was well established. Some bridges were not designed to carry the increasing traffic volume experienced today. Cracks occurred primarily at details that were not sufficiently addressed in the previous AASHTO design specifications, in particular at locations subjected to out-of-plane distortion. This paper provides an overview of Texas DOT practice in the repair of steel bridge fatigue cracking, including Texas DOT–sponsored research studies and their successful implementation in bridge rehabilitation. Case studies presented in this paper include the Fair Park bridges in Dallas, the IH-20 bridges in Midland County, the SH-225 bridges at Sims Bayou, the Intracoastal Canal Bridge in Jefferson County, and the IH-345 bridges in Dallas.