Date of Award:


Document Type:


Degree Name:

Master of Science (MS)


Civil and Environmental Engineering

Committee Chair(s)

Paul J. Barr


Paul J. Barr


Marc Maguire


Joseph A. Caliendo


The Utah Transportation Center in conjunction with the Mountain Plains Consortium sponsored a study to investigate the performance, and condition of a steel, twin, I-girder bridge. The bridge is located on the Idaho-Oregon border near Payette, Idaho, and was designed to carry traffic over the Snake River.

Bridge Diagnostics Inc. was contracted by the Idaho Transportation Department to perform a live-load test on the bridge. This testing included the placement of 62 gauges that measured the response of the bridge as heavy trucks were driven across it.

A 3-D finite-element model of the bridge was generated and compared to the results of the bridge response due to live-load. When the finite-element model accurately predicted the results of the live-load test, it was used to further investigate the behavior of the bridge. The load distribution between the various substructure components was quantified, and compared to the predicted bridge behavior according to methods recommended in the AASHTO bridge design specifications.

Understanding bridge behavior is important in determining the needs for bridge maintenance and replacement. This, in turn, will potentially reduce public health risk, and save significant funds for bridge owners.