Prototype Tire-Shred Embankment Construction

Abstract

The New York State Department of Transportation constructed a pilot project using tire shreds as embankment fill. The prototype section, measuring 200 m in length, used approximately 2500 metric tons of tire shreds as the core of the embankment section. The tire-shred zone had a maximum thickness of 3 m, and the tire shreds were covered with 1.5 and 1.0 m of embankment fill on the top and sides, respectively. The entire section was then surcharged with an additional 1.25 to 2.50 m of fill. After 4 months, the surcharge was removed to subgrade elevation, the granular base was placed, and the section was paved. The project was designed in accordance with the guidelines to limit internal heating of tire-shred fills distributed by the Federal Highway Administration. The tire shreds were produced by a hook and shear shredder, placed in the fill with a front-end loader, and compacted with a smooth-drum roller. Instrumentation of the prototype section was monitored both during and after construction. In all, 10 settlement platforms, 15 temperature sensors, 2 groundwater collection systems, and a groundwater observation well were installed and monitored. Settlements were as expected based on previous projects, and temperature measurements showed that there was no internal heating of the tire shreds. A unique incentive program developed jointly by the state’s Department of Transportation, Department of Economic Development’s Empire State Development Corporation, and Department of Environmental Conservation resulted in 267,000 tires being removed from abandoned stockpiles.