Effect of Cement Kiln Dust and RBI Grade 81 on Engineering Properties of Plastic Clay

This paper deals with plastic clay (CH) treated with cement kiln dust (CKD) and roadbuilding international Grade 81(RBI 81). Geotechnical properties including consistency limits, compaction characteristics, unconfined compression strength (UCS), California-bearing ratio (CBR) and consolidation properties are investigated before and after treating the soil. The effects of CKD and RBI 81 on geotechnical properties are found to be very significant. The consistency tests result in the various mix proportions of CKD, RBI 81, with clay soils indicates the low plastic (CL) in nature. The maximum dry density significantly improved with these cementations materials. The UCS increases with increase in curing time and achieves maximum strength. The mix of CKD and RBI 81 with clay soils of the compression index reduced considerably. For pavements having high compressible subgrade especially in rural areas, these materials are very useful due to significant improvement in CBR values. They are durable in terms of maintenance of the pavements as well. Scanning electron microscopy (SEM) observations on original clay and treated mix presented. The SEM image shows the formation of impermeable CSH and CAH gel. The mix which was studied can be used for rural and low-cost construction road infrastructures.