Geotechnical Performance of Encapsulated and Stabilized Stone Columns in a Collapsible Soil

Abstract

Recent investigations have opened the prospect of using stone columns in collapsible soils through the use of geofabric encapsulation. However, the effectiveness of this type of ground improvement in such soils is still inconclusive. The main objective of this paper is to investigate the geotechnical performance of encapsulated and stabilized sand columns installed in a collapsible soil layer and subjected to full saturation. Fully penetrating sand columns, encapsulated in a geofabric and stabilized with some cementing agents, were tested. A Terram T3000 geofabric was used as the encapsulating material. The cementing agents used were lime, lime with fly ash, and cement. They were used in different proportions, in this case 4%, 8%, and 12%, respectively. The carrying capacity and settlement characteristics of the reinforced and stabilized columns were examined. Furthermore, analytical models were developed to predict the carrying capacity and settlement of encapsulated and stabilized sand columns. Validation of the developed models with the experimental results of the present investigation and with some data reported in the literature was also considered.