CH 5 over Interstate 80
Henry County, Illinois
CH 5 Slope Stabilization
HEI was selected by the Henry County Highway Department to provide Phase I and II engineering services for the correction of an embankment failure in the northeast quadrant of the interchange between Interstate 80 and Henry County Highway 5 just south of Atkinson, Illinois. County Highway 5 is classified as a Major Collector with an average daily traffic of 1,700. The correction of this slope failure was critical to keep the roadway open to traffic as a multitude of over the road semi trucks use this exit to access an adjacent truck stop.
HEI coordinated all of the Phase I environmental reviews and Phase II design engineering for the reconstruction of this embankment. The environmental review, and eventual construction, of this project location was aggravated by an identified wetland within the northeast infield of the interchange ramps, as well as a retention basin north of the exit ramp and south of the first commercial drive.
HEI developed plans and specifications to reconstruct this embankment under live traffic through a series of embankment benches with furnished excavation of better quality soils. In addition, this embankment slope was flattened to help increase stability. The county highway drainage, and the general site drainage, were all taken into account with the design including reconstructed ditches at the toe of the embankment slopes. In all, this project involved over 3,500 cubic yards of furnished excavation and over 1,250 tons of rock fill for construction. The project was constructed under live traffic with staged construction.