Experimental investigation of solidifying desert aeolian sand using microbially induced calcite precipitation

摘要

In this study, five different concentrations of solidification solution (0.5, 1.0, 1.5, 2.0 and 2.5 mol/L urea-CaCl2) were used to solidify desert aeolian sand by microbially induced calcite precipitation (MICP). As the concentration of solidification solution increased, the CaCO3 content increased, sand density increased, permeability was reduced and the unconfined compressive strength increased. Formation of CaCO3 was the primary cause of changes in the sand's properties. Specifically, CaCO3 filled the pores between the sand particles and the pore volume decreased. The CaCO3 formed in response to low concentrations (i.e., 0.5-1.0 mol/L) and high concentrations (i.e., 1.5-2.5 mol/L) of urea-CaCl2 solution played different roles in solidification of the structures. (C) 2018 Elsevier Ltd. All rights reserved.