Technical and environmental feasibility of interlocking concrete pavers with iron ore tailings from tailings dams.

Abstract

The present paper evaluates the technical and environmental feasibility of using iron ore tailings (IOTs) as fine aggregate in the production of interlocking concrete blocks. Initially, environmental, chemical, and physical characterizations of the tailings were carried out. Pavers with IOTs replacing natural aggregate in proportions from 10 to 80% were manufactured and subjected to physical analyses (expansion, porosity, and water absorption), environmental analyses (leaching and dissolution), as well as mechanical tests (compressive strength and surface abrasion). Test results of the IOT pavers were compared to conventional ones and to standard limits. The IOT pavers showed physical and mechanical properties significantly similar, or superior, to the conventional ones, and all within the requirements for regular traffic. Therefore, IOT are technical and environmentally feasible to be used in the production of precast concrete blocks. This reuse also contributes to the reduction of the social and environmental impacts associated to tailings dams.