The effect of different additive materials on the engineering properties of soils

Stabilization is the improvement of geotechnical properties of clays such as consistency, strength and compression by using pozzolanic additives. In this study, variations in the consistency, texture and the strength of high-plasticity due to the effects of different typies and proportions of additives were investigated. For this purpose, in the laboratory studies, slaked lime, silica fume, fly ash, tuffs with acidic and basic characteristics were used as additives. According to the results obtained from the study, it was determined that the liquid limit (LL) and plasticity index (PI) values decreased significantly in the samples where the unnatural and natural additives were used together. The images obtained by SEM studies showed that in the cases where the maximum decrease in PI values occurred, significant agglomeration occurred as a result of pozzolanic reaction. As per the outcomes of the studies conducted, it was determined that the cure application improved strength and strength parameters and that, following stabilization, if the reduction in the Plasticity Index (PI) in additive samples was more than 60%, the Cohesion (c) and Angle of Internal Friction (Φ) and, hence, Unconfined Compressive Strength (qu) significantly increased and that, in order for qu values to increase, there should be an increase in the values of both c and Φ. The results obtained from the study showed that the best outcomes could be obtained if slaked lime or fly ash were used or when acidic tuff and basic tuff additives were used along with them. Keywords: Stabilization, pozzolan, tuff, strength parameters, agglomeration