Effect of Spacing between Stone Columns on the Behavior of Soft Soil

Soil improvement by stone columns is extensively used, especially for the soft ones. This because of their efficiency and no environmental impact. Several factors affect its in improving mechanical properties soil, most important these are spacing, length, diameter columns. In this study, finite element method was used to study impact spacing between on amount settlement bearing capacity soil. The comprises three different spaces (s) that were taken relation columns’ (d), which (s/d= 3, 4, 5). addition, types sectional shape column involved circular, rectangular, square sections with lengths (L/d=2, 6, 8, 10). results showed effective when vertical load greater than 30 kN/m2, below this, there effect spacing. general, decreases, increases decrease becomes a more pronounced longer length All short (L/d=2) same 271 mm at distance (s/d=5), decreases 7.4, 6.6, 8.9% (s/d=3) rectangular respectively. case long (L/d=10), improves about 27.5% drop 18% (s/d=5). A slight soil's associated improvements soil treated 6.0, 6.5, 4.7% sections, respectively, changing from (s/d=5) (s/d=3). Whereas they become increasing (L/d=10) be 7.9, 9.2, 6.4%.