Use of Cement Kiln Dust for the Stabilization of Soils

Stabilization of soils is an effective method for improving soil properties and pavement system performance. Cement kiln dust (CKD) represents an alternative to the traditional stabilization agents of lime, cement, and Class C fly ash. As with the other additives, cement kiln dust can be expected to vary in effectiveness depending on the soil type. A total of eight different soils with classifications of CH, CL, ML, SM, and SP were subjected to a series of durability tests, including freeze-thaw, wet-dry, and leach testing, to evaluate the relative performance of CKD as a stabilization agent. Results were compared with previous findings for the same soils stabilized with lime, cement, and fly ash. Atterberg limits and strength tests were conducted before and after selected durability tests. Relative values of soil stiffness were also tracked over a 28-day curing period using the soil stiffness gauge to evaluate ongoing reactions. The results provide guidance on which soil types can be expected to have significant improvements in performance with the addition of CKD.