IMPACTS OF FREEZING-THAWING AND WETTING-DRYING CYCLES ON A SILT STABILIZED BY LIME AND WASTE SILICA

摘要

The main objective of this research is to investigate the effects of lime and waste silica fume additive on a silt and its utilization on railway subgrades stabilization. For this purpose, lime and waste silica fume were added to the silty soil in different contents at the soil optimum moisture; then the California Bearing Ratio (CBR) tests were conducted on the soil samples to estimate the favorable mixture design. At the next step, a selected sample was chosen to be exposed to wetting-drying and freezing-thawing cycles. The results showed that the lime-silica fume additive increases the CBR values of the soil significantly. Furthermore, the first wetting-drying cycle enhances the samples' CBR value, but subsequent wetting-drying cycles decrease the sample's CBR value. Moreover, freezing-thawing cycles reduce the samples' CBR values.