Expansive soils occurring in arid and semi-arid climate regions of the world cause serious problems to civil engineering structures. Several attempts are being made to control the swell-shrink behavior of these soils. The major environmental challenge is the disposal of the byproduct solid wastes. Waste materials such as Rice Husk Ash and Stone Dust are selected as additives to the soil. The admixture improves the geotechnical properties of joint mixture. (Soil-lime-rice husk ash and soillime-stone dust, Soil-cement-rice husk ash and soil-cement-stone dust). In this context an attempt is made to study expansive soil mixed with Rice Husk Ash (RHA) and stone dust. In the present study by taking earlier study results of lime and cement stabilization percentage as 8% and to that RHA and stone dust was mixed in increments of 2% ranging from 2 to 12% are added and subjected to different curing periods such as 7, 14, 28 and 56 days was studied by conducting unconfined compressive strength (UCS) studies on the samples for various curing periods. There was a considerable increase of UCS from 0 to 7 days and the constant rate of increase in strength from 7 days to 28 days may be attributed to reaction between RHA – Lime-Cement and CaOH present in natural soil as soon as flocculation starts i.e. 7 days and was primarily dominated by lime content and curing. Addition of RHA and Stone dust further improved strength of the mix.
