The effect of reclaimed sand and lime on the properties of black cotton soil in context of subgrade improvement

Stabilization remains a prominent approach for improving soil’s strength and subgrade qualities. The utilization of reclaimed sand in black cotton soil stabilization is still under investigation. Shrinkage and swell properties of soil, low bearing capacity, increased compressibility, and high moisture vulnerability are all common geotechnical traits of expansive soils. This study looks at the effect of recovered sand mixed with lime on the properties of black cotton soil for stabilization. The consequence of the addition of lime, and reclaimed sand on geotechnical parameters of black cotton soil was investigated using a variety of tests including Atterberg's Limits, California Bearing Ratio (CBR), Proctor Compaction, and Unconfined Compressive Strength (UCS). With the addition of lime, and reclaimed sand, the optimal moisture content increases, with the addition of lime and reclaimed sand, maximum dry density reduces, and CBR and UCS value increase. The highest results, however, were obtained with a mix treatment consisting of 6 lime, and 40% reclaimed sand. For cost comparison, a one-lane and two-way road with a length of one kilometer and a width of 3.5 m is used. The cost of embankment, and subgrade material, compaction and pavement surfacing has been left out of the analysis. According to the calculations, the usage of reclaimed sand from building and demolition debris results in a total cost savings of 17.74%.