Evaluation of Cement-Stabilized Mine Tailings as Pavement Foundation Materials

Waste disposal is an important topic for cities today. We have shown for the first time how to make sewage sludge disposal safer, more environmentally friendly and still to obtain some benefit from it, namely energy, from its organic content. The main purpose of this paper is to present a laboratory tests results based on investigation carried out on the tailings of Boukhadra Mine in Algeria, in order to find out their suitability for use in road embankments, and pavement foundations. Three types of tailings, namely as marl, limestone and iron ore wastes, were initially tested to find the most suitable of them for application in pavement structures. Having presented more compliant properties, limestone waste, after being treated with cement, was tested with modified Proctor compaction, compressive strength (CS) and California Bearing Ratio (CBR) tests. At 2% intervals, the cement content of the mixtures is varied from 0 to 6%. Test results showed that an increase of cement content in the mixture would increase maximum dry density and decrease optimum moisture content of the compacted mixture. The increases in CBR and CS values qualifying the mixtures for use in Algerian pavement foundation were also noted, indicating that the limestone waste from Boukhadra Mine has the potential to be directed to an outlet for recycling.