Investigating the Effects of Freeze-Thaw Cycles on the Shear Behavior of Sand Stabilized by Microbial Induced Carbonate Precipitation (MICP) Method

Abstract

The MICP method is used as a novel procedure for soil stabilization. One of the important things is to assess how long-lasting new additions are for stabilizing soil. Therefore, this study assesses the impact of freeze-thaw cycles on the strength of sandy soil stabilized using the MICP method. Additionally, variables like confining pressure, the number of freeze-thaw cycles (NC) for FT, temperature changes (T) during each cycle, and the length of the cycles are evaluated. For this purpose, the consolidated-undrained static triaxial tests are used. Taguchi method is applied to design the tests and propose a relationship for predicting the specimens' deviatoric strength (q). The results show that FT cycles reduce the deviatoric strength of samples stabilized by the MICP method. Also, the results of analysis of variance (ANOVA) indicated that the confining pressure, number of freeze-thaw cycles, minimum temperature of freeze-thaw cycles, maximum temperatures of freeze-thaw cycles, and duration of freeze-thaw cycles have, respectively, the highest importance and effect on the q value.