Geosyntec and Colleagues from the University of California, Davis were honored with the 2016 Telford Premium Award for best paper in Ground Improvement, the journal of the Institution of Civil Engineers (ICE), Volume 168, Issue 3, August 2015, pp 206-216.
The paper is titled "Field-scale bio-cementation tests to improve sands." It documents field trials of bio-cementation for erosion control at a project site in northern Saskatchewan in 2012. Geosyntec provided support in experiment design, project management, geotechnical testing, process engineering, and production of bacterial cultures.
Geosyntec contributors Brian Martinez (California), Christopher Hunt (California), Len deVlaming (Ontario), David Major (Ontario) and Sandra Dworatzek (Ontario) collaborated with Professor Jason DeJong and doctoral candidate Michael Gomez of UC Davis.
Geosyntec continues to stay involved as this technology travels the path from research to practice. With support of two of its internal action groups, the Geotechnical & Geoenvironmental Engineering Action Group (GEAG) and the Technology Advisory Council (TAC), Geosyntec is a leadership level member of the new National Science Foundation Center for Bio-mediated and Bio-inspired Geotechnics (CBBG), and we have a current internal TAC award that is being used to further our involvement in the research being done by the CBBG member universities, which include UC Davis, Arizona State University, Georgia Institute of Technology, and New Mexico State University.
AbstractMicrobially induced calcite precipitation (MICP) is a bio-mediated cementation process that improves the geotechnical properties of soils through the precipitation of calcite at soil particle contacts. This study presents a field-scale, surficial application of MICP to improve the erosion resistance of loose sand deposits and provide surface stabilisation for dust control and future re-vegetation. Three test plots were treated with a bacterial culture and nutrient solutions at varying concentrations, and a fourth test plot served as a control. Improvement was assessed to a depth of 40 cm using dynamic cone penetration (DCP) testing and calcite content measurements. The most improved test plot received the lowest concentrations of urea and calcium chloride and developed a stiff crust measuring 2·5 cm thick, which exhibited increased resistance to erosion. DCP testing and calcite content measurements indicated improvement to a depth of approximately 28 cm near the targeted depth of 30 cm. The results suggest that further optimisation of solutions and techniques could render MICP viable for larger-scale applications.
For more information or to download the article, visit: Proceedings of the Institution of Civil Engineers - Ground Improvement