This DLZ project in Boone County, Kentucky involved the rehabilitation of the pavement for the Ohio River Bridge. It included 2.85 miles of rural interstate four-lane PCC pavement on I-275 from the Ohio River Bridge to just east of the KY 8 interchange. The pavement rehabilitation utilized an 11” JPC overlay on a 1” asphalt bond breaker course to minimize reflective cracking. However, remedying a settlement problem at the west-end of the Bridge, led to removal of approximately 1700’ of PCC pavement. Then, it was replaced full depth with 18-¼”asphalt pavement on 6”DGA on 12”No.2 crushed stone with perforated pipe underdrains. This route carries heavy volumes of traffic (2006 ADT of 29,271 projected to be 79,757 by 2026 with 20% trucks).
The Maintenance of Traffic Schemes (MOT) Strategy
DLZ studied two separate pavement repair alternates utilizing three different Maintenance of Traffic Schemes (MOTs). The MOT strategy selected shifted all traffic to one roadway using a reversible lane with a moveable concrete barrier wall. This was a first for Kentucky. Since the traffic flow on this I-275 section was heavily directional during AM and PM, this particular MOT strategy was successful. Because it provided two lanes in peak direction of travel at appropriate times, it saved $2,000,000 over a conventional method. This MOT plan included five construction phases and the use of four median crossovers and eight slips ramps. Additionally, the MOT plan accommodated the full depth replacement on the Ohio River approach in 16 calendar days.
The twin I-275 bridges over KY 8 were jacked/raised in elevation to meet new JPC Overlay to avoid digouts at their approaches. Other items of work included the installation of pavement edge drains, replacement of all guardrail, installation of flexible delineators and raised pavement markers, adjustment of several median box inlets, and rehab all ramps on KY 8 interchange.