Use of Biocementation for Slope Stabilization of Levees

While levee embankments are the first line of defense for urban flooding, recent flooding events have revealed widespread slope instability of embankments around the country that can lead to levee failures. This work aimed to improve the slope stability of earthen levees by strengthening the soil through the use of a biologically-inspired technique called biocementation. The major objective of this study was to determine the optimal and most practical biocementation method that results in the best performance of levee slopes under various flooding conditions. A novel biocementation method called bacterial enzyme-induced calcite precipitation (BEICP) was tested. This method differs from the well-studied microbial-induced calcite precipitation (MICP) method mainly in the size of the biological agent (whole bacterial cell vs. enzyme), which influences the agent’s mobility in soils of different grain sizes. The BEICP methods for soil strengthening were optimized in laboratory-scale column experiments. The optimized methods were then used to construct levees in an experimental flume system. The results indicated that the BEICP treatment resulted in significant strengthening of the surface of the soil specimens, which were measured as increases in unconfined compressive strength. The strengthened samples were able to resist erosion for a longer time period under overtopping scenarios of water challenges with high water velocity in a flume. Therefore, BEICP offers a sustainable and economical method for treatment of soil surfaces to improve erosion resistance. The results of this study will help mitigate flooding events that could cause major issues in transportation infrastructure and traffic safety.

• Record URL:
  https://intrans.iastate.edu/research/completed/use-of-biocementation-for-slope-stabilization-of-levees/
• Record URL:
  https://mtc.intrans.iastate.edu/research/completed/use-of-biocementation-for-slope-stabilization-of-levees/
• Record URL:
  https://intrans.iastate.edu/app/uploads/2018/12/biocementation_for_levee_slope_stabilization_w_cvr.pdf
• 

Language

• English

Project

• Status: Completed
• Funding: $162233
• Contract Numbers:

  DTRT13-G-UTC37

• Sponsor Organizations:

  Midwest Transportation Center

  Iowa State University
  2711 S Loop Drive, Suite 4700
  Ames, IA  United States  50010-8664

  Office of the Assistant Secretary for Research and Technology

  University Transportation Centers Program
  Department of Transportation
  Washington, DC  United States  20590

  Iowa State Universtiy

  Civil, Construction, and Environmental Engineering
  394 Town Engineering
  Ames, Iowa  United States  50011
• Managing Organizations:

  Iowa State University, Ames

  Institute for Transportation
  2711 South Loop Drive, Suite 4700
  Ames, Iowa  United States  50010-8664
• Performing Organizations:

  Iowa State University, Ames

  Institute for Transportation
  2711 South Loop Drive, Suite 4700
  Ames, Iowa  United States  50010-8664
• Principal Investigators:

  Ikuma, Kaoru

  Cetin, Bora

  Rehmann, Chris

  Ong, Say Kee

• Start Date: 20160901
• Expected Completion Date: 20181130
• Actual Completion Date: 0

Subject/Index Terms

• TRT Terms: Flood protection; Infrastructure; Levees; Slope stability; Soil stabilization
• Subject Areas: Bridges and other structures; Highways; Hydraulics and Hydrology; Materials; Safety and Human Factors;

Filing Info

• Accession Number: 01618658
• Record Type: Research project
• Source Agency: Midwest Transportation Center
• Contract Numbers: DTRT13-G-UTC37
• Files: UTC, RiP
• Created Date: Dec 2 2016 12:23PM