GEOTECHANICAL PROPERTIES AND STRENGTH CHARACTERISATION OF BAUXITE RESIDUE

Red mud is a solid waste generated in the Bayer process of alumina production from the aluminum industries. About 0.8-1.5 tons of red mud is generated per ton of alumina production. Annual world production of 70 million tonnes red mud has a serious effect on the environment (RUSAL 2013). The major Producers in India are Hindalco, Nalco, Malco, Balco and Indal added to this, in absence of any technology storage of this unutilized red mud takes vast usable land. Red mud is a perilous waste which contains high levels of residual alkalinity and toxic heavy metals viz. silica, aluminum, iron, calcium, titanium, as well as an array of minor constituents, namely: Na, K, Cr, V, Ni, Ba, Cu, Mn, Pb, Zn [1]. They occupy a vast area of land which does not support any kind of vegetation because of their hostile nature vegetation growth. Because of the huge volume of the red mud being generated as a byproduct from the alumina industry it makes them nearly difficult to contain them and thus causes serious disposal problems [2]. Red mud has high maximum dry density (MDD) in comparison to other materials, due to high specific gravity. Based on crumb test, double hydrometer tests and turbidity test red mud is found to be highly dispersive [3]. Addition of fly ash, phosphogypsum and red mud to the zinc leach residue drastically reduces the heavy metal content in the leachate and could be used as liner materials [4]. Stabilization of Red mud by the addition of various amounts of hydrated lime, condensed silica fume and limestone to Jamaican red mud is suitable for use as a construction material, without employing Portland cement as binder [5]. Red mud and cement–red mud materials can be successfully used for the stabilization of clay liners in geotechnical applications [6]. A higher value of CBR i.e., 35% was obtained for 25% GGBS (Ground Granular Blast Furnace Slag) at 28 days curing period. Hence Red mud stabilized with GGBS can be used as sub base, base course and also sub grade material for road construction [7][8]. The CBR value obtained for 10% lime at 28 days is 25% so that it can be used as sub grade and sub base material in road construction [7][8]. The present research work was related to study on the geotechnical characterization of red mud and stabilized with in civil engineering applications.