IDOT is requesting that towns schedule in-depth inspections of bridges
Illinois Department of Transportation:
Although the Department has not yet seen a report detailing the reasons for this deficiency, we suspect that a combination of moderate corrosion at the fracture location, combined with extreme temperature swings in the last two weeks, contributed to the fracture.
The dapped beam connections may also occur on material types other than steel. If you are aware of this detail or any similar details for structures under your jurisdiction, please send the structure number and a copy of the existing plans to the following e-mail address: IDOT.LocalBridgeUnit@illinois.gov.
Because the entire state saw similar temperature swings, we also ask that you schedule an In-Depth inspection of such structures as soon as possible to provide assurances to the public that this detail has been recently inspected, and you do not anticipate any similar issues. If the inspection shows the bridge may need a repair or retrofit, please let us know at the above e-mail address.
We appreciate your attention to this matter and look forward to working with you to correct any issues found.