Performance of Encased Silica-Manganese Slag Stone Columns in Soft Marine Clay

• Main Authors: S. Siva Gowri Prasad, P.V.V. Satyanarayana
• Format: Article
• Language: English
• Published: Universitas Indonesia 2019-10-01
• Series: International Journal of Technology
• Subjects: bulging; encasement; geotextile; marine clay; silica-manganese slag; stone column
• Online Access: http://ijtech.eng.ui.ac.id/article/view/2094

Stone columns are the most suitable and economical ground improvement technique for soft soils. Stone columns accelerate the consolidation process, thereby increase the stiffness of the soil. This increase may not be sufficient because of the less lateral confinement, which leads to excessive bulging. The strength of the composite soil can also be increased further by encasing the column with geotextile. In this paper, model tests were conducted on end-bearing stone columns with geotextile encasement and compared with the unreinforced (plain) stone columns. The stone columns were prepared by placing the silica-manganese slag, sand and were reinforced with geotextile with different encasement lengths of D, 2D, 3D, and 4D (D is the stone column diameter; i.e., 5 cm). The tests demonstrated that the engineering behavior of the soil was improved by introducing the silica-manganese slag (when compared with conventional stone columns) and also with encasement. Bulging can also be reduced by providing encasement beyond the zone of bulging.