In Illinois and Indiana, inspections after the Minnesota bridge collapse didn't turn up any serious problems in the states' bridges and no bridges were shut, spokesmen for the state transportation departments say.
Andrew Dietrick, spokesman for the Indiana Dept. of Transportation (INDOT), said in an email, “After initial visual inspections of the state’s 13 bridges with a similar design type as the I-35 bridge (steel truss), nine were selected for additional inspection. The inspection contract specified in-depth inspections with load-rating analysis.”
Dietrick says that none of the bridges was shut, “but one of the nine inspected was restricted to 8 tons. Inspectors found corrosion because of a drainage issue.”
Both states are receiving shares of the additional $1 billion for bridge reconstruction contained in the omnibus spending bill enacted last December. Illinois DOT (IDOT) spokesman Mike Claffey said in an email that the state’s General Assembly included its $28-million portion of the $1 billion, plus a $7-million state match in IDOT’s fiscal 2009 highway program budget. The budget took effect on July 9.
Claffey adds: “While the money is available, IDOT has not made a final determination on which bridges will be funded with this money. One of the stipulations Congress imposed on these additional funds is that the money has to be used on bridges that are not currently programmed, so you cannot accelerate existing projects.”
Neither state has changed its bridge inspection requirements or programs.
Illinois DOT’s Claffey notes that the Federal Highway Administration has issued three directives or advisories to states since the Minnesota collapse. The first recommended the immediate inspection of all deck truss bridges; the second advised states to limit construction activities on bridges if that activity could overload any structural members; and the third strongly encouraged states to check capacity of gusset plates.
Claffey says that IDOT supports the FHWA recommendations and has carried out the first two. He adds that IDOT is a member of a National Cooperative Highway Research Program-FHWA research project that “will develop policies and procedures for the analysis and load rating of truss gussets” to meet the requirements of FHWA's third notice.
Claffey says: “IDOT is currently in the process of inspecting all truss bridges, specifically measuring dimensions and thicknesses of each gusset plate. Inspectors are also documenting all areas of rust and deterioration in each gusset plate. This field data will be used to analyze and load rate all gusset plates when this research project is complete.”
He adds: “IDOT has implemented policy that requires additional inspections within 7 months of the anticipated letting date for specific groups of structures including structurally deficient or fracture critical bridges. These inspections ensure timely information regarding deterioration is incorporated into contract plans and provides competitive bidders with a more accurate scope of work based on current conditions.”
Indiana DOT hasn’t changed its bridge inspection requirements or programs in the aftermath of the I-35W collapse, says Dietrick. He adds that that INDOT hasn't added to its inspection staff. “We have 24 qualified, full-time bridge inspectors on staff,” he says. “That is adequate to maintain our schedule of inspections for the state inventory.”
But in Illinois In Illinois, DOT spokesman Claffey says: “The effort to collect the data on all truss gussets is beyond the current capacity of in-house inspection staff. IDOT has hired a number of consultants to assist in collecting this data.”