A predictive model based on the experimental investigation of collapsible soil treatment using nano-clay in the Sivand Dam region, Iran

As a kind of problematic soil, collapsible soils can withstand relatively high stress in an unsaturated state. Still, upon wetting and being saturated, such soils show a significant sudden reduction in volume, causing damage to the structures. One of the environmentally friendly materials used to treat collapsible soils is the nano-clay as potential stabilizers. The present study investigates the nano-clay effect on the soil collapse treatment in the Sivand region, Fars Province, Iran. Further research proved to achieve fine dispersion of added nano-clay between the soil particles appropriately through the wet mixing method. To investigate effective soil collapse behavior parameters, 72 reconstructed samples with different water content, dry density, applied vertical stress, and nano-clay contents are tested using the static compaction method. The results indicate that soil collapse behavior is almost completely fixed using only 5% nano-clay. It has also been concluded that the collapse potential increases with reducing water content, dry density, nano-clay contents, while it has an increase if applied vertical stress increases. The extracted test results are used as a database to develop an efficient model to predict the soils’ collapse potential. Additionally, the parametric and sensitivity analyses confirm the model output with the test results.