Electrokinetic Stabilization of Soft Soil Using Carbonate-Producing Bacteria

• Published in: Geotechnical and geological engineering 2014-08, Vol.32 (4), p.739-747
• Main Authors: Keykha, Hamed A., Huat, Bujang B. K., Asadi, Afshin
• Format: Article
• Language: English
• Subjects: Anodes; Bacteria; Calcium; Calcium carbonate; Calcium ions; Carbonates; Cathodes; Civil Engineering; Clay; Clay soils; Earth and Environmental Science; Earth Sciences; Electrokinetics; Electromigration; Electroosmosis; Geotechnical Engineering & Applied Earth Sciences; Hydrogeology; Mechanical properties; Original Paper; Polarity; Porous media; Shear strength; Soft clay; Soil; Soil bacteria; Soil mechanics; Soil microorganisms; Soil porosity; Soil properties; Soil stabilization; Soil strength; Terrestrial Pollution; Urea; Waste Management/Waste Technology
• ISSN: 0960-3182; 1573-1529
• DOI: 10.1007/s10706-014-9753-8

The carbonate (CO 3 −2 ) produced by Sporosarcina pasteurii was injected electrokinetically to enhance the mechanical properties of soft clay soils. In this method the Ca 2+ was injected into the anode chamber and moved towards the cathode by electromigration and electroosmotic flow. Then the released CO 3 −2 from a blend of bacteria and urea was injected into the cathode chamber. The CO 3 −2 ions were moved from the cathode to the anode under electromigration mechanism. The CaCO 3 was precipitated in the presence of calcium in porous medium of the soil, and consequently increased the shear strength of the soil. The polarity reversal was applied to have a homogeneous distribution of CaCO 3 .