CH 17 over Tributary to Spoon River Replacement

Knox County, Illinois

CH 17 over Tributary to Spoon River Replacement

HEI was selected by the Knox County Highway Department to provide Phase I and II engineering services for the replacement of the structure carrying County Highway 17 (1800 E Road) over a Tributary to Spoon River. The project is located approximately 5 miles east of Gilson, Illinois. County Highway 17 is classified as a rural major collector with an average daily traffic of 125.

This project involved the removal of the existing double barrel corrugated metal culvert pipe structure. The existing CMPs were each 9 feet in diameter with an upstream concrete headwall for an overall structure length of 27 feet and width of 65 feet. The CMPs were showing significant section loss and were very near the point of failure. The roadway over the culvert was beginning to pothole as the pavement base and fill above the culvert was quickly eroding through the ceiling of the pipes. The replacement structure is a single-span precast, prestressed, 27-inch concrete deck beam structure. The structure is supported on concrete spill-thru pile bent abutments. The new structure is 68 feet in length and 28 feet in width with no skew. The project was constructed under full road closure.