US-59, Leflore County, Oklahoma (Koss #62)

Leflore County
Leflore County

Completed in early summer of 2011, this project is located in LeFlore County, Oklahoma just south of the Kerr Reservoir Lock and Dam. This project included grading, drainage, bridges, and surfacing on US Highway 59. This was the next extension of the US-59 reconstruction efforts south of Sallisaw, Oklahoma, extending 8.006 KM to the intersection of Highway 9 and US-59. The north bound lanes were constructed in 2010 while traffic remained on existing two lane US-59. The typical section consisted of lime treated subgrade, 17.8 m separator fabric, 200 mm aggregate base, 100 mm cement treated base, 175 mm variable depth shoulder, and 225 mm mainline concrete pavement. Once traffic was switched to the new northbound lanes, the Sooner Division left Oklahoma to pave in Kansas while pavement removal and grading resumed on the southbound lanes. Upon completing pavement removal on the southbound lanes, the existing road bed was found to be so unstable the Oklahoma Department of Transportation suspended subgrade modification in mid-December until a new typical section could be drafted to mitigate the poor soil conditions. Work resumed early January of 2011 with a new typical section requiring an additional 100 mm of aggregate base as well as 50,600 m² geo-textile materials. To construct the new typical section, two CMI Autogrades were employed to span 18.4 meters to place both aggregate base and cement treated base. This allowed for seamless construction of the cross section. In total, Koss Construction placed 256,000 m² separator fabric, 120,000 MG aggregate base, 194,000 m² cement treated base, and 179,000 m² concrete pavement.