Behavior of Sand Compaction Columns Installed in Cohesionless Deposits

Abstract

A critical appraisal of the reviewed literature revealed that there are very limited studies available on the strength characteristics focusing on the load-settlement behavior of sand compaction columns (SCCs) when installed in cohesionless deposits. The method, though contemporary to the reputed stone column technique, is not yet studied rigorously in the available past studies, more precisely on the load-bearing characteristics when compared to the latter. Therefore the present study focuses on studying the behavior of multiple column composite foundation supported by sand compaction columns installed in loose to medium dense sands on a lab-scale numerical model. The study is carried out using commercially available finite element (FE) code 3D PLAXIS. Spacing to diameter ratio (S/D) ranging from 1.5 to 3.5 and initial relative density (RD) from 30 to 60% was adopted to study the changes in the load-settlement behavior of the improved deposit. Extending the FE model to further parametric study, the effect of angle of internal friction of the column sand and diameter of the column on the bearing capacity and settlement characteristics were analysed with and without normalization. From the results obtained, it is found that, for the considered FE model, the improved deposit with 3D spacing between the SCCs behaves distinctly different from all other cases analyzed.