Efficient road base material from Kazakhstan's natural loam strengthened by ground cooled ferrous slag activated by lime production waste

Abstract

A scientifically based disposal of all industrial and municipal wastes is the only solution for the problem of the rapid and constant increase in environmental pollution and the associated climate change, with inevitable catastrophic consequences for our planet. The present study proposes such scientifically based method for the use of two types of industrial waste – ground cooled slag of ferrous metal and lime production waste – as a binder for natural loam for road base construction with complete replacement of traditional layers from natural sand and rubble. The axial compression strength of the developed materials in 3-day age samples reached 3.27 MPa, in 28 days–6.95 MPa, 180 days–13.39 MPa, and 550 days–16.44 MPa, very high water and frost resistance, and rather low linear expansion, meeting the demands for 1st class construction materials of the Kazakh norms. It has been established, by a set of modern complementary methods (X-rays diffractometric analysis, X-rays fluorescence analyses, scanning electron microscopy, Energy-dispersive spectroscopy, Atomic absorption spectroscopy laser micro-mass analyses), the synthesis of new formations, mainly amorphous, which are binding the particles of the initial components. The achieved mechanical properties enable the application of these composites also as building materials, such as unburned bricks and blocks with high environmental and economic efficiency.