Lightweight fill, used to replace granular fill on a weak subgrade, is of particular interest to road construction. Scrap tires benefit from their lightweight and thermal insulation properties and hydraulic conductivity. Road construction with scrap tires provides a means of disposing of the tires and helps reduce the instability of construction over soft and frost-susceptible soils. However, most research has been focused on using 150-mm or smaller shreds as a lightweight fill in road construction, and there is a lack of technical data on the use of large-size shredded rubber tires. A large-size tire shred embankment, constructed to provide access to a gravel pit near the city of Winnipeg, Manitoba, Canada, is described. The thermal and mechanical behavior of large-size tire shreds is examined by conducting field temperature monitoring and laboratory and field compressibility testing. The thermal behavior of the tire shreds, established from on-site automated temperature measurements, has shown the thermal coefficient of the tires to be 0.2832 W/m times deg C. In the compressibility analysis, three sizes of shred (300 mm, 150 mm, and 50 mm) are examined. The elastic modulus of the shredded tires is determined as a function of the bulk density of tires. A model is used to predict and verify the compressibility of the tire shred embankment based on the laboratory testing of tire compressibility.
Abstract