Changes in Chemical Concentration of Silty Clay Added with Lime and Nanolime

Stabilization of clayey soils with lime has shown that small amounts of lime considerably improve the workability whereas larger amounts of lime only improve the strength which requires several months or years and is thus considered the long-term treatment. Nanoparticles are excellent candidate materials for soil improvement. Due to their smaller dimensions, nanoparticles possess a very high specific surface and react more actively with other particles in the soil matrix. The existence of even a minute amount of these nanoparticles can result in extraordinary effects on the engineering properties of soil. Thus, this study was carried out to validate the chemical effectiveness of nanolime additives as soil stabilizer. Lime and nanolime were chosen as additive to investigate its reactivity on silty clayey soil. The results of pH test revealed that the pH increased proportionally, changing from 4.07 (acidic range) to about 7.85 and 12.47 for a dose of 1.0% of lime and nanolime, respectively. X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), X-ray fluorescence (XRF) and field emission scanning electron microscopy (FESEM) tests were run for original and treated soil samples to characterize the mechanisms of chemical improvement. Nanolime shows superiority in soil improvement compared with lime even at the dosage of 0.5%. The results indicate that nanoparticles have higher specific surface area and this will lead to a larger amount of water encompass the outer surface of particles. Due to higher ability of nanolime to flocculate and agglomerate, it could fill the micro and nano pores as well which dramatically enhances the chemical properties of the soil.