Effect of pyrophyllite on behavioural strength of clayey soil

Abstract

The clay soil consists of minerals like montmorillonite which shrink and swell when the moisture content is altered because of which the bearing capacity of soil get decreased, which causes differential shrinkage of soil can leads to failure of super-structure. These weak soils can be stabilized by adding chemical minerals to improve its properties. The probability of stabilizing the clay soil using pyrophyllite in different proportions like 5%, 10%, 15% and 20%. Initially the compaction characteristic on adding pyrophyllite was done by standard proctor compaction test and the strength character were done based on unconfined compression test at various curing periods such as 0, 3, 7, 14 and 28th days and California bearing ratio test done on 4 and 7thdays. Compaction character test shows that on addition of pyrophyllite content, OMC increase whereas MDD decreased. UCC strength was noted after a curing period of 28 days the strength gain was maximum, the rate of development in the strength however decreased in 20% of pyrophyllite content with the soil showed the maximum strength when compared to the other percentages. Also, on adding admixture the CBR value increases, but not beyond 15% for soil sample 1 whereas CBR value increased till 20% for soil sample 2. From the results, the admixture of 15% can be selected as a nominal percentage which can be used in soil to enhance the soil character. In addition to strength parameter, these admixtures are also an eco-friendly and economical additive in soil stabilization process.