Use of microfluidic experiments to optimize MICP treatment protocols for effective strength enhancement of MICP-treated sandy soils

Wang，Yuze1,2; Konstantinou，Charalampos3; Soga，Kenichi4; Biscontin，Giovanna5; Kabla，Alexandre J.5

2022

10.1007/s11440-022-01478-9

Acta Geotechnica   影响因子和分区

1861-1125

1861-1133

Microbially induced calcium carbonate (CaCO) precipitation (MICP) has been extensively studied for soil improvement in geotechnical engineering. The quantity and size of calcium carbonate crystals affect the strength of MICP-treated soil. In this study, microfluidic chip experiments and soil column experiments were conducted to optimize MICP treatment protocols for effective strength enhancement of MICP-treated sandy soils. The microscale experiments reveal that, due to Ostwald ripening, longer injection intervals allow crystals to dissolve and reprecipitate into larger crystals regardless of the concentration of cementation solution. Even though a cementation solution input rate of 0.042 mol/l/h is sufficient to maintain a high chemical transformation efficiency, a further reduction in the input rate by about four times resulted in an increase in the size of crystals produced by the end of treatment from about 40 to 60 μm. These findings were applied in soil column experiments. Results showed that significantly larger crystals and higher soil strength were achieved when the normalized rate of cementation solution injection was reduced from 0.042 to 0.021 mol/l/h. Crystal size and soil strength increased slightly more when the normalized input rate was further reduced from 0.021 to 0.010 mol/l/h. This study demonstrates how data from microscale microfluidic experiments that examine the effects of injection intervals and concentration of cementation solution on the properties of calcium carbonate crystals can be used to optimize MICP treatment in macroscale sand soil column experiments for effective strength enhancement.

MICP optimization Microbially induced calcium carbonate (CaCO3) precipitation (MICP) Microfluidics Microscale properties Strength enhancement

SCI

英语

通讯

WOS:000763852900001

2-s2.0-85125558222

Scopus

1.Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou),Shenzhen,China
2.Department of Ocean Science and Engineering,Southern University of Science and Technology,Shenzhen,China
3.Department of Civil and Environmental Engineering,University of Cyprus,Nicosia,Cyprus
4.Department of Civil and Environmental Engineering,University of California,Berkeley,United States
5.Department of Engineering,University of Cambridge,Cambridge,United Kingdom

Wang，Yuze,Konstantinou，Charalampos,Soga，Kenichi,et al. Use of microfluidic experiments to optimize MICP treatment protocols for effective strength enhancement of MICP-treated sandy soils[J]. Acta Geotechnica,2022.

Wang，Yuze,Konstantinou，Charalampos,Soga，Kenichi,Biscontin，Giovanna,&Kabla，Alexandre J..(2022).Use of microfluidic experiments to optimize MICP treatment protocols for effective strength enhancement of MICP-treated sandy soils.Acta Geotechnica.

Wang，Yuze,et al."Use of microfluidic experiments to optimize MICP treatment protocols for effective strength enhancement of MICP-treated sandy soils".Acta Geotechnica (2022).