Volume 15, Issue 3 (September 1992)
Techniques for Estimating the Longevity of Lime-Treated Expansive Clays
Two techniques are presented that investigate the possibility of estimating the longevity of lime-treated expansive clays subjected to leaching. The techniques are based on analyzing calcium concentrations and pH changes within accelerated leached laboratory specimens and their leachates during the leaching process. The accelerated leach times required to produce specific calcium concentrations and pH in the laboratory are converted to actual field leaching (or percolation) times by using developed time scale factors.
The techniques are tested for validity by correlating estimated calcium concentrations and pH values of field lime-treated clays to the actual results of field lime-treated clay layers of various known ages. The correlations showed that pH estimations were within an average of 13% of measured values, while estimated calcium concentrations remaining in the soil-lime layers were within an average of 18% of measured values.