Characterization of blast furnace slag for road projects

Abstract

The present study evaluated the potential use of Blast Furnace Slag (BFS) as forming material of untreated granular layers in pavement (e.g. base, subbase and subgrade), and as stone aggregate in the manufacture of asphalt mixtures. For that purpose, tests of characterization, X-ray diffractometry (XRD), X-ray fluorescence (XRF) and imaging in a scanning electron microscope (SEM) were executed on the BFS. As a general conclusion is reported that the BFS can be used in the formation of unbound granular layers of subbase. As granular base material, its use would be recommended on roads with low traffic volumes or with thick asphalt layers and as a selected material, in tertiary roads that support light traffic. In the case of HMA is not recommended to use the coarse fraction of the BFS as a stone aggregate. However, the obtained results indicate that the fine fraction shows good characteristics to be used in the production of the mastic of such mixtures.