ABSTRACT
To control volume changes of soils tending to swell and soften in increased moisture conditions or to shrink and dry-cracked in decreased moisture environment stabilization with lime or fly ash could be used. Laboratory tests were performed in order to evaluate the engineering properties obtained when clayey subgrade soils are stabilized with lime or fly ash. The plasticity has been improved with all additive percentages. After mixing with lime, substantial increases in the California Bearing Ratio value have been obtained. The values were higher than those measured in soil-fly ash mixtures. The increase in optimum moisture content and the maximum dry density reduction acted subsidiarily to the increased California Bearing Ratio values, particularly at high lime or fly ash contents. Good correlation was found between the bearing capacity values and the cone penetrometer indications of both the untreated soils and their admixtures with lime and fly ash (r = 0.7 and 0.88).
