Jackson, GA Recycled Plastic Modular Roundabout System - 2 Year Status

Adam Lankik

FHWA funded ZKxKZ to develop a rapidly installable, modular, recycled plastic roundabout system intended to compete favorably with conventional concrete, asphalt and stone roundabout materials in installation time and installed cost. The modular system provides roundabout engineers with other benefits, including the ability to be driven over at any time during installation, simplifying traffic management. Five plastic prototypes are currently installed in North America. This presentation will describe experiences with the first DOT-funded prototype, installed in Jackson, GA, in December 2017, as well as planned upgrades currently under development with new R&D funding from USDOT and the Department of Defense. Compared to the original plastic baseline, the updated technology is expected to cut installation time in half, and further reduce cost. Discussion of the evolution of anchoring technology, including advancements to ground anchors and plastic plugs, will be featured. A unique benefit of the modular system is its ability to quickly and inexpensively allow local DOTs to reshape installed center and splitter island design details. Modifications made to reduce vehicle entry speed and improve post-installation traffic flow at the Jackson, GA, installation site will be described.

The objective of this presentation is demonstration of the benefits of using a modular plastic roundabout system compared to current, more difficult to modify, conventional construction materials. With the modular installation approach, roundabout practitioners can easily and cost effectively modify an existing modular roundabout intersection design based on site-specific empirical data, gathered after the original installation, to change traffic behavior for improved traffic safety and/or throughput. The target audience includes municipality leadership, traffic engineers, roundabout designers and anyone involved in roundabout technology, installation and maintenance.

Roundabout design principals and installation approaches are still developing as implementation increases and lessons learned are applied. Many intersections offer unique design challenges that are not fully understood at the time of installation, and have the potential to change as demand and vehicle interactions change. Communities and roundabout practitioners may feel apprehensive about transitioning stop light or sign controlled intersections to roundabouts. The ability to cost effectively make near-real-time modifications to installed roundabout geometry in response to actual post-installation performance data provides roundabout practitioners a useful new tool to cost effectively improve roundabout performance, and reduce community apprehension to roundabouts.