Lime type and quality in relation to the stabilization of soils with different gradations and clay materials

This paper reports the results of a laboratory investigation involving the addition of nine hydrated limes (four high calcium, one dolomitic, three semi hydraulic and one hydraulic) and one portland cement to seven soils (a sand, a silty loam, one naturally occurring kaolinitic clay loam, three artificially blended montmorillonitic clay loams of varying plasticity and a heavy lacustrine clay. The results showed that lime is a more effective stabilizing agent than cement with soils in which montmorillonite is the predominant clay mineral; the high calcium and semi hydraulic limes were the most successful limes with these soils. With lime soil mixtures containing kaolinitic clays the lime treated specimens gave lower strength values than the cement treated ones; the semi hydraulic type proved to be the most effective of the limes. Generally the strength results obtained with low clay content soils confirmed that for successful lime stabilization a soil must contain a considerable proportion of clay size material.