Combined Use of Ladle Furnace Slag and Rice Husk Ash as a Supplementary Cementitious Material

Ladle Furnace Slag (LFS) is a solid waste from steel production that can be used in civil construction due to its high content of calcium oxides (> 50% CaO), contributing to the sustainability of both industries. Seeking to study its function as a supplementary cementitious material, the objective of this work was to determine the properties of coating mortars with the replacement of Portland Cement (PC) by 30% LFS combined with the pozzolanic effect of Rice Husk Ash (RHA). Prismatic specimens were produced in a 1:6 mixture proportion (PC:sand) and subjected to mechanical tests and determination of the dynamic modulus of elasticity. The results indicated that the replacement provided a reduction in mechanical strength, however the presence of LFS+RHA was beneficial to improve water retention. These changes were caused by the bigger surface area of RHA grains and the higher CaO content, in relation to the reference mixture.

Keywords:
industrial waste; binder; portland cement; mortar; sustainable construction