1Central Soil and Materials Research Station, New Delhi
Online Published on 04 February, 2022.
Ground granulated blast slag (GGBS) is the granular by-product produced by steel manufacturing processes. Industrial granular solid waste materials like fly-ash, red mud and slag can be engineered chemically or mechanically to achieve desirable properties as geo-materials (Karol 2003). These engineered geo materials have a huge range of geotechnical applications such as ground improvement materials, landfill materials for highway and railway embankment, as land fill liners at engineered waste disposal facilities and as stabilizing agent for natural slopes. It can also be used in construction of tailling dam which is used to store by-products of mining operation. There have been number of studies/cases like soft soil stabilization using ground granulated blast furnace slag, characteristics of core materials mix of GGBS with locally available soil used in slime dam/tailing dam construction, soil stabilization using ground granulated blast furnace Slag, use of GGBS as an alternative to natural sand etc. From these studies, investigators concluded that use of GGBS results in improvement of physical and strength properties of soil.
GGBS is of silty type materials having silt content around 15–20%. GGBS is non plastic having liquid limit around 30 to 33%.Maximum dry density (MDD) and optimum moisture content of GGBS varies from 12 g/cc to 16 g/cc and 21% to 26% respectively. As per IS 16714 - 2018, the minimum fineness should be 320 m²/kg. The main chemical constituents of GGBS are CaO, SiO2, Al2O3, Fe2O2 etc.
It has been reported that with the increase of GGBS content specific gravity increases whereas Liquid limit, plastic limit, shrinkage limit and plasticity index decreases. Hydraulic conductivity of Brahamaputra river sand found to be decreases with addition of GGBS. Studies also indicate that unconfined compressive strength also increases in general. GGBS have been used in stabilization of black cotton soil, soft soil etc. If other engineering properties like consolidation, shear strength, in presence of different percentage of GGBS can be studied, than it will be easier to declare it as Geomaterial.
