PLEASANT VALLEY DRIVE IN OWENSBORO, KY USES TX GEOGRID TO SOLVE PROBLEM WITH PAVEMENT CONSTRUCTION
As part of the contract to build a new regional hospital Pleasant Valley Drive in the City of Owensboro and Daniels Lane in Davies County required reconstruction. The contract had no provision for stabilizing soft soils below the conventional pavement section and the section only had 4″ of aggregate base course to place prior to the first lift of asphalt. Proof rolling the prepared subgrade resulted in rutting between 1″ – 2″. Therefore, an alternate pavement section was needed that could do the following:
- Meet or exceed the original pavement section structural number (SN), and therefore loading.
- Allow for the immediate construction of a pavement over a subgrade that was rutting up to two inches.
- Maintain as close as possible the original pavement block thickness to account for set elevations
- Not incur additional costs to the contractor to construct the new pavement.
An alternate pavement was designed using Tensar’s Spectra Roadway Improvement System, which reduced the asphalt base course from 10.75″ to 6.5″, and increased the aggregate base course from 4 ” to 12″ (with a layer of Tensar TX5 geogrid). By designing the new pavement section with 12″ of aggregate (and Tensar TX5 geogrid), the contractor was able to get compaction over the soft subgrade, and the structural contribution of the stiffened aggregate layer (due to the TX5 geogrid) allowed for a reduction in the asphalt thickness. Over $100,000 in savings was realized by utilizing Tensar’s solution, versus stabilizing the subgrade with chemicals or undercutting and constructing the original pavement section that was planned for the project.