County Highway 12 over Mauvaise Terre Creek
Scott County, Illinois
County Highway 12 Bridge Replacement

HEI was selected by the Scott County Highway Department to provide Phase I, II, and III engineering services for the replacement of the structure carrying County Highway 12 over Mauvaise Terre Creek along with roadway realignment through the project area. HEI was successful in securing Illinois Special Bridge Funding for the county for this project. The project is located approximately two miles northeast of Exeter, Illinois. County Highway 12 (Chapin Road) is classified as a rural minor collector with an average daily traffic of 150.
This project involved the removal of the existing three-span structure consisting of a reinforced concrete deck on continuous steel girders supported by open abutments and three column concrete piers on concrete footings. The existing structure was 174 feet in length and 22-ft in width and showing significant signs of distress in the superstructure elements. The project also included nearly one quarter mile of roadway realignment to correct a blind switchback curve at the project location. This included significant right of way acquisition, tree removal, environmental coordination, and embankment construction.
The replacement structure is a three-span precast, prestressed, concrete deck beam structure consisting of 27-inch deck beams for one span and 33-inch deck beams for the remaining two spans. The structure is supported on fully encased steel H-Pile bent piers and concrete spill-thru pile bent abutments. The new structure is 225-ft in length and 30-ft in width with a 35 degree skew. The new roadway embankment construction consisted of earthen fill topped with a 12-inch Type A aggregate base course and three inches of hot mix asphalt for the final driving surface. The project was constructed under full road closure.

