The Influence of Compactive Effort on Compacted Lateritic Soil Treated with Cement Kiln Dust as Hydraulic Barrier Material

The paper evaluates the suitability of lateritic soil treated with up to 10 % cement kiln dust (CKD) by dry weight of soil for the construction of waste containment facilities compacted at three energy levels. Laboratory tests were carried out on specimens prepared at molding water contents −2, 0, +2 and +4 % of the optimum moisture content and compacted with British standard light, West African standard or ‘Intermediate’ and British standard heavy (BSH) energies. Index, hydraulic conductivity, volumetric shrinkage and unconfined compression tests were carried out. Results obtained show improvement in index properties with CKD treatment. Regulatory criteria of maximum hydraulic conductivity value of 1 × 10−9 m/s, minimum unconfined compressive strength of 200 kN/m2 and maximum volumetric shrinkage strain (VSS) of 4 % were satisfied with a minimum 7.5 % CKD treatment when specimens were compacted at BSH energy level. The overall acceptable zone for the treated soil was achieved with 10 % CKD treatment for specimens prepared at molding water content range of 13.5–21.3 % and compacted with BSH energy.