Preserving the Service Life of a Bridge Threatened with Fatigue Cracking

摘要

The IH-345 viaduct in downtown Dallas, Texas, has experienced fatigue cracking that resulted in 20 years of increased inspection, monitoring, and repair of the steel superstructure. The steel framework is made of mainly longitudinal girders and transverse floor beams. This article addresses advancement in structural engineering as a practical solution of reaching beyond the codified provisions for design, evaluation, and rehabilitation of highway steel bridges using advanced analytical methods. Finite Element models, calibrated to field instrumentation results through strain/displacement measurements for specific truck loading, were used to analyze the structural performance, find the crack formation mechanisms, and ultimately develop retrofit schemes.