Effects of iron ore tailings (IOT) and lime on engineering
properties of problem laterite
Umar*, S.Y. and
Elinwa, A.U.
Civil
Engineering Programme, Abubakar Tafawa Balewa University,
P.M.B. 0248, Bauchi, Nigeria.
Abstract
The results
of experimental investigation of lime and iron ore tailing (IOT)
admixture on lateritic soil are presented. Preliminary
investigations classify the untreated soil as A-6. Compressive
strength and soaked California Bearing Ratio (CBR) values of 200 kN/m2
and 4%, respectively, further connotes the inadequacy of the soil in
terms of engineering requirements. Stabilization test results showed
that hydrated lime is effective in modifying the properties of the
soil. The addition of IOT to the soil – lime mixtures yielded soil
with enhanced properties that met the sub-base and base-course
requirement of conventional specification. Specifically, 7 – day
compressive strength increased from 600 kN/m2 for
specimens treated with 8% lime only to 1120 kN/m2 for
specimens treated with 6% lime and 15% IOT. This value met the 7
days 1035 kN/m2 Unconfined Compressive Strength (UCS)
evaluation criterion recommended for economic range of lime content
for adequate stabilization of problem soils. The CBR improved from
4% for the untreated soil to 70% for soil specimens treated with a
combination of 8% lime and 15% IOT.
