A laboratory study was undertaken to evaluate the effect of ageing on the properties of regina clay treated with 2 and 4 percent quicklime. ageing is generally referred to as the time interval between the addition of lime and water to the soil and the compaction of the mixture. Regina clay, a highly expansive clay, was selected for this study because it forms a common subgrade material in saskatchewan. As a result of this study, it was found that ageing had a pronounced effect on the properties of the treated soil. The properties also depended on the percentage of lime. The results indicate that both density and strength decreased as a result of an increased ageing period for the treated samples prepared using constant compactive effort. However, the reduction in strength could be eliminated or could even result in an increase if the treated specimens with low percentages (e.g., 2 Percent) were subjected to an increased compactive effort.Nevertheless, the results show that increasing the compactive effort could not eliminate the reduced strength for samples treated with higher percentages of lime (e.g., 4 Percent) and increased ageing (e.g., 24 Hr). Increased compaction may well lead to a lower strength as a consequence of overcompaction. ageing appears to have had no significant effect on swell for treated samples prepared by both constant and increased compactive efforts, and little effect as well on the plasticity index.
Samenvatting