Finite Element Modeling and Health Monitoring of the Ironton Russell Truss Bridge
The Ironton Russell Bridge is a vital link economically and socially, and merges the cities of Ironton, Ohio and Russell, Kentucky across the Ohio River. Built in 1921 the bridge has been a picture of regular inspections, retrofits and repairs. Periodic inspections have identified a progressive deterioration in the condition of the downstream and upstream truss members, floor system, and non redundant hanger and pin details. Visual inspections of the main trusses have revealed repairs in the form of weld details that do not conform to standard welding techniques specified in the ANSI/AASHTO/AWS Bridge Welding Codes. It was concluded that these weld details are a serious concern from the point of view of fatigue. This coupled with the constant deteriorating physical state of the bridge forced the inspectors to recommend a reduction in the allowable load on the bridge's through truss spans from 23.4 tons to a negligible 3 tons. A posting of 3 tons would have severely affected the daily ADT using the bridge as it is the only means of crossing the river for many miles north and south, and would have thus hampered normalcy in the region. The Ohio Department of Transportation contracted UCII in 1999 to perform field tests on the bridge to provide a better assessment of the structural stability of the bridge. Since then the bridge as well as the monitoring system has undergone significant wear and tear necessitating an up gradation of the currently installed sensor layout. In 2007 UCII was given the responsibility maintenance and upgrade of the existing system to fully represent the current state of the bridge. Also included in the contract was the aspect of the instrumentation of the approach spans 14 and 15. The thesis aims to provide a detailed documentation of the process involved in the design of the health monitor including the finite element modeling, and the rating of steel members and the concrete deck.
School:University of Cincinnati
School Location:USA - Ohio
Source Type:Master's Thesis
Keywords:truss bridge rating finite element modeling
Date of Publication:01/01/2009