Volume 14, No. 2, 2020
Received: 2020/04/25, Accepted:
Authors:
Sapna Devendra; Prathap Kumar, M. T.;
Abstract:
Soils consisting of montmorillonite mineral are highly expansive upon exposure to water, leading to reduction in shear strength. Studies have indicated that cement kiln dust as an admixture to black cotton soil (BC soil) that contains montmorillonite improves both compaction and plasticity index. Addition of unground cement clinker (UCC) alters gradation of stabilized soil, leading to better compaction. The objective of the present study is to use both cement kiln dust (CKD) and unground cement clinker (UCC) as a sustainable admixture to
improve plasticity, compaction and shear strength of BC soil. It was found that 12% CKD was optimum in terms of reduction in plasticity with corresponding improvement in compaction. Optimum dosage of CKD was used to comparatively assess the effect of adding unground cement clinker. 12% UCC in combination with optimum CKD indicated denser packing, leading to improvement in compaction properties of BC soil. Shear strength of BC soil admixed with optimum dosage of CKD and UCC with 0-28-day curing period was determined in order to understand the effect of change in compaction characteristics of CKD and UCC-admixed
BC soil. Shear strength of BC soil admixed with optimum dosage of cement kiln dust (12% CKD) and optimum dosage of unground cement clinker (12% UCC) was significantly greater when compared to all the
combinations used in the study. This indicates that the addition of both cement kiln dust and unground cement clinker leads to sustainable soil improvement.
Keywords:
Cement kiln dust, Black cotton soil, Unground cement clinker, Compaction, Unconfined compressive strength.