Comparative evaluation of freeze and thaw effect on strength of BEICP-stabilized silty sands and cement- and fly ash-stabilized soils


Tung Hoang T. H. , Do H., Alleman J., Cetin B., Yalçın Dayıoğlu A.

ACTA GEOTECHNICA, 2022 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Publication Date: 2022
  • Doi Number: 10.1007/s11440-022-01612-7
  • Journal Name: ACTA GEOTECHNICA
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, INSPEC, Civil Engineering Abstracts
  • Keywords: Bacterial enzyme induced carbonate precipitation (BEICP), Cement, Fly ash, Freeze and thaw, Microbial induced carbonate precipitation (MICP), Sand, Silty sand, CALCIUM-CARBONATE PRECIPITATION, ENGINEERING PROPERTIES, MECHANICAL-PROPERTIES, PORTLAND-CEMENT, BEHAVIOR, LIME, WATER, PERFORMANCE, PERMEABILITY, IMPROVEMENT
  • Istanbul Technical University Affiliated: Yes

Abstract

This paper addresses a soil bio-stabilization technique using bacterial enzyme-induced calcium carbonate precipitation (BEICP) as an alternative to previous conventional methods including microbial-induced carbonate precipitation and plant-derived enzyme-induced carbonate precipitation. The extracted urease enzyme of viable S. pasteurii was used as a biological source along with calcium chloride and urea to solidify sandy soil and silty sand soil. The bio-treated soil columns were subjected to freeze and thaw (F-T) cycling for a durability evaluation. Engineering properties of bio-cemented soil including unconfined compressive strength, calcium carbonate contents, moisture contents, porosity, permeability, and microstructure were examined before and after the F-T durations. It was found that although bio-stabilizer was able to increase a frost duration of soil, the F-T cycling significantly impacted on the compressive strength of bio-treated soil, due to a formation of microcracks. This investigation has revealed that the BEICP method provided a similar capacity in F-T resistance of soil as using the traditional Portland cement stabilizer, whereas the class F fly ash did not improve F-T durability of medium dense soil.