Subgrade improvement with mixed lime and cement as additives

Abstract

The study deals with the utilization of mixed lime and cement for enhancing subgrade soil properties. Most of the research has been carried out utilizing the lime and cement individually. Less investigation has been done on mixing lime and cement and then adding in the soil to gauge its effect on the properties. The research work aims at investigating the effect of mixing the additives instead of using them individually. A series of tests were carried out, including Atterberg’s limits, modified Proctor and California Bearing Ratio in accordance with BS EN 1377-(2–4-9):1990 standards. The soil used for the research work was taken from the construction site of Paisley Museum in Paisley-Scotland. The mixture combinations adopted for testing were: Control/Untreated Sample, Lime 3% and Cement 1.125%, Lime 6% and Cement 2.25%, Lime 9% and Cement 3.375% replacement. The results showed interesting features, as the lime and cement utilized in combination showed a significant improvement in the values of the CBR (%) in comparison to previous research, where the lime or cement were used separately in the soil. With the increase of the percentage replacement of lime and cement combined, the CBR (%) with respect to the untreated samples of soil showed also significant increase. For a penetration of 2.5 mm, the increase in the soil CBR (%) was not significant in the beginning but after adding more stabilizer materials we have seen the values increasing up to 36%. On the other hand the increase was around 21 % for the CBR penetration of 5.0 mm.