TY - JOUR
T1 - Liquefaction resistance of biocemented loess soil
AU - Sun, Xiaohao
AU - Miao, Linchang
AU - Chen, Runfa
AU - Wang, Hengxing
AU - Wu, Linyu
AU - Xia, Jinxin
N1 - Funding Information:
The authors thank the valuable comments from the reviewers. This study was funded by the National Natural Science Foundation of China (Grant No. 51578147), Fundamental Research Funds for the Central Universities (Grant No. 2242020R20025), and the Science and Technology Department of Ningxia (Grant No. 2020BFG02014).
Publisher Copyright:
© 2021 American Society of Civil Engineers.
PY - 2021/11/1
Y1 - 2021/11/1
N2 - Microbially induced calcite precipitation (MICP) is currently appraised to improve sandy soils, but only a few studies use it to solidify loess soil. MICP solidification tests and undrained cyclic triaxial tests were conducted to study the liquefaction resistance of MICP-solidified loess soil samples. The results showed that because calcium carbonate (CaCO3) cemented loess soil particles and filled voids in samples, the permeability coefficients of treated samples all decreased. However, the change pattern of the permeability coefficient of samples treated with various conditions was different. For the solidified samples, the liquefaction resistance was improved significantly, and increased treatment cycles resulted in the improvement of the liquefaction resistance. Adding bacterial suspension and the cementation solution together made the sample with initial density of 1.4 g/cm3 have higher liquefaction resistance. However, for samples of 1.5 and 1.6 g/cm3, adding bacterial suspension and the cementation solution separately also achieved better liquefaction mitigation effects. Increasing total solution volume per treatment cycle improved the liquefaction resistance of the solidified samples. With the increase of CaCO3 content, the number of cycles before liquefaction (NL) and residual strength (τr) exponentially increased, while the damping ratio (D) exponentially decreased. Moreover, the linear corrections between specific gravity and CaCO3 content, NL, τr, and D can be established for MICP-solidified loess soil. In addition, significant corrections also existed between plasticity index and CaCO3 content, NL, τr, and D. Results in this work had a great significance and provided the foundation for the application of the MICP technique for liquefaction mitigation of loess soil.
AB - Microbially induced calcite precipitation (MICP) is currently appraised to improve sandy soils, but only a few studies use it to solidify loess soil. MICP solidification tests and undrained cyclic triaxial tests were conducted to study the liquefaction resistance of MICP-solidified loess soil samples. The results showed that because calcium carbonate (CaCO3) cemented loess soil particles and filled voids in samples, the permeability coefficients of treated samples all decreased. However, the change pattern of the permeability coefficient of samples treated with various conditions was different. For the solidified samples, the liquefaction resistance was improved significantly, and increased treatment cycles resulted in the improvement of the liquefaction resistance. Adding bacterial suspension and the cementation solution together made the sample with initial density of 1.4 g/cm3 have higher liquefaction resistance. However, for samples of 1.5 and 1.6 g/cm3, adding bacterial suspension and the cementation solution separately also achieved better liquefaction mitigation effects. Increasing total solution volume per treatment cycle improved the liquefaction resistance of the solidified samples. With the increase of CaCO3 content, the number of cycles before liquefaction (NL) and residual strength (τr) exponentially increased, while the damping ratio (D) exponentially decreased. Moreover, the linear corrections between specific gravity and CaCO3 content, NL, τr, and D can be established for MICP-solidified loess soil. In addition, significant corrections also existed between plasticity index and CaCO3 content, NL, τr, and D. Results in this work had a great significance and provided the foundation for the application of the MICP technique for liquefaction mitigation of loess soil.
KW - Caco 3 content
KW - Cyclic triaxial test
KW - Liquefaction mitigation
KW - Loess soil
KW - Microbially induced calcite precipitation (micp)
UR - http://www.scopus.com/inward/record.url?scp=85113383416&partnerID=8YFLogxK
U2 - 10.1061/(ASCE)GT.1943-5606.0002638
DO - 10.1061/(ASCE)GT.1943-5606.0002638
M3 - Journal article
AN - SCOPUS:85113383416
SN - 1090-0241
VL - 147
JO - Journal of Geotechnical and Geoenvironmental Engineering
JF - Journal of Geotechnical and Geoenvironmental Engineering
IS - 11
M1 - e0002638
ER -