Effect of silica fume on the undrained strength parameters of dispersive

Dispersive soils are one of the problematic soils such as swelling and collapsible soils and they are common in many countries of the world. Due to dispersive soils, significant problems arise in road embankments and earth dams. Therefore, the use of such soils is possible with treatment. Silica fume (SF) as a waste material has been used in concrete production instead of partially cement, in the stabilization of expansive soils and in many civil engineering applications for different purposes. Within the scope of this study, to determine the dispersibility behavior of the soil sample, crumb test was performed. SF additive was used to improve the soil sample, which was determined to have high dispersibility. The compaction properties of the soil specimens mixed with SF in different proportions (0, 5, 10, 15, 20, 25 and 30%) were determined by the standard Proctor test. Crumb tests were performed to assess the dispersibility potential of the prepared specimens, and also unconsolidated and undrained (UU) triaxial tests were carried out to evaluate the strength parameters. UU experiments were performed under 20 kPa, 40 kPa and 60 kPa effective cell pressures on specimens cured for 1, 7 and 28 days because stabilization occurred at shallow depths in field applications. As a result, it was determined that the dispersibility feature of the soil sample was treated and the strength properties were improved depending on the SF content.