Geotechnical Characteristics of Bauxite Residue Sand Mixed with Crumbed Rubber from Recycled Car Tires

Abstract

The re-use of waste materials is an essential step in creating a sustainable future, and research into the re-use of different byproducts has often led to new materials that provide superior service or greater economy than those traditionally used. This paper aims to investigate the use of new mixtures of bauxite residue sand and crumbed rubber from recycled car tires, as fill material. In Australia alone, 20,000 tons of bauxite residue sand is produced daily as a by-product from the Aluminum industry and 20 million recycled car tires are annually disposed, leading to environmental health and hazard problems. In this paper, the geotechnical characteristics of the new mixtures are investigated under static and dynamic loading conditions. A series of laboratory experiments are conducted, including sieve analysis, compaction, permeability and static as well as repeated loading consolidateddrained triaxial tests. In addition, numerical modeling using the finite element method is used to examine the feasibility of the new materials in two geotechnical engineering applications, including slope stability and pavement design. The results indicate that the bauxite residue sand-tire crumb mixtures have a good potential for use as lightweight fill material in geotechnical engineering applications.