KY 15 - Perry County, KY

Though the focal point of this 1.2-mile roadway realignment is improving safety, the project also showcases Palmer’s experience designing a variety of structure types for KYTC. Structures designed for this project include two PCI-Beam bridges, a culvert extension, a retaining wall, and layout for over 200 ft of MSE wall.

The largest structure on the project carries KY 15 over Perry Park Road, the North Fork of the Kentucky River and KY 550. With a length of 700 ft, the five-span 93-ft-wide structure carries five lanes of traffic and is skewed 40 degrees to parallel the river. Piers are founded below the anticipated scour depths on large diameter drilled shafts that transition to individual columns.

Large breastwall abutments bookend the bridge, one founded on spread footings, and the other on driven piles. Hybrid beams were selected to minimize superstructure depth to help meet vertical clearance requirements for the underpassing roads.

Another PCI-beam bridge is located at the Morton Boulevard interchange.  This two-span 150-ft-long structure also features low-profile, hybrid beams to meet vertical clearance requirements over KY 15. The substructure consists of integral abutments independently founded on driven piles behind MSE walls with a pier in the median of KY 15 founded on drilled shafts.

Reconfiguration of Ramp A leading to KY 550 required a 320-ft-long extension of the existing 5’ x 4’ RCBC below KY15. The new geometry required a change in grade from the existing to new culvert by over 3%.

To provide necessary sight distance, the access to Willie’s Way along the new KY 15 alignment required reconfiguration, which resulted in the design of a 150-ft-long cantilever retaining wall. To maintain access to critical businesses along Willie’s Way during construction, the wall’s footing was stepped, minimizing any excavation behind the wall.

Finally, the MSE walls wrapping the integral abutments of the Morton Boulevard Bridge extend 200 feet behind Abutment 1 and allow for the new slip ramp providing access from Morton Boulevard to KY 15. Palmer chose an MSE wall configuration, rather than extending the bridge, for economic benefits.