An Investigation into the Geotechnical Properties of Soil-Tyre Mixtures

Abstract

The work presented in this paper investigates the potential of using waste shredded tyre in soil-tyre mixtures for specific engineering applications. Bentonite, kaolin and kaolin-lime were used as the base clayey soil types. Soil-tyre mixtures containing up to 20% tyre were tested for compaction, unconfined compression strength, permeability and leachability. The results show that the compacted dry density, strength and permeability decrease with the introduction of the tyre and decrease further as the amount and size of tyre particle is increased. The permeability results, which contradict other published work, could mean possible application as landfill cover and landfill liner material. The TCLP leaching test indicated higher concentrations of heavy metals in the leachates than drinking water standards with the exception of one of the kaolin-lime-tyre mixtures. Results from less severe leaching tests than the TCLP test should be investigated before firm conclusions are made. These results are encouraging for use of waste shredded tyre in soil-tyre mixtures. It could prove to be both economical and a safe method of the disposing of rubber.

Keywords:

• reuse of waste material
• soil-tyre mixtures
• soil stabilisation
• leaching tests
• geotechnical properties