Model Tests on Swelling Behavior of an Expansive Soil with Recycled Geofoam Granules Column Inclusion

Column techniques are preferred for the deep stabilization of problematic soils. Earlier studies revealed the significance of using chemicals (lime/cement) as column material. This paper presents the swelling behavior of an expansive soil with recycled geofoam granules column (GGC) inclusion formed using the beads from waste expanded polystyrene (EPS) blocks. In the current study, the grouping effect of GGC, the model test tank studies were carried out on expansive soil with varying diameters and the number of columns by changing plan configurations. Several swell tests were performed on a developed circular steel tank with an internal diameter of 450 mm and height of 180 mm. An experimental test was conducted to determine the performance of GGC inclusions in expansive soil, by adopting two different diameters (40 mm and 75 mm) along with formed GGC density of 15 kg/m3. The influence of varying diameter of GGC, spacing between the columns, and increasing the number of columns were experimentally investigated in the circular steel tank. The test results were analyzed and compared for the soil sample with and without GGC inclusion (i.e., soil alone, SA). The results of the tests revealed that by increasing the diameters and number of columns, the swelling potential is decreased due to GGC inclusion. Further, these findings provide basic information about the design and installation of GGC in field-level tests with some practical limitations.