Design Speed Minimum Radii

‘Design Speed Minimum Radii’ shows the turning radii of speed. Governed by safety, the geometric road design for interchanges and intersections governs that more speed = larger radii. This graphic overlaps the radii as provided by AASHTO at 7 different speeds. Red lines indicate the minimum turning radii for roads with super-elevation; the sectional tilt of the road surface to counter the centrifigal force of turning at a speed. The curves in cyan show the minimum radii necessary at the same speeds without the super-elevation, which need to be larger without the help of the super-elevation.

This work is part of Emerging Terrain's Stored Potential project, which began as a desire to re-purpose the grain elevator at 33rd and Vinton Streets. Emerging Terrain partnered with the elevator owners, city agencies, neighborhood associations and various community organizations to make the project happen. They solicited artists to submit designs addressing the themes of land use, food, and agriculture, a selection of which were printed on polyester mesh banners and installed on the exterior of the elevator silos. Up-lit at night, the banners were viewable to drivers passing on I-80, transforming the derelict structure into a super-size, drive-by art gallery. The project culminated with an outdoor dinner party for 500 people, all of whom were seated at an 800-foot-long table near the base of the installation.