Stabilisation of dune sand using electric arc furnace dust

Abstract

Dune sand is one of the predominant soils in the world, particularly in the Arabian Peninsula and North Africa. In order to use these soils in constructions, pre-treatment of sand is essential. Though the usage of cement for stabilising sand has long been the practice to achieve the required strength, it is not cost effective and its manufacturing consumes a lot of energy. Consequently, it would be noble to use industrial by-products, often considered as waste materials, such as electric arc furnace dust (EAFD), in the stabilisation of sand. This research reports the potentiality of using EAFD for improving the strength of dune sand. Specimens, mixed with 2% cement and mixed with 5, 10, 20 and 30% EAFD plus 2% cement, were evaluated using unconfined compressive strength, soaked CBR and durability tests. Results of this investigation indicated that dune sand stabilised with 20 and 30% EAFD plus 2% cement has been qualified as a construction material for sub-base in rigid and flexible pavements, respectively, as per ACI requirements. Scanning electron microscope, energy dispersive X-ray analysis and backscattered electron images, in addition to, XRD analysis were used to identify the various phases in the sand-2% cement-30% EAFD mixture.