Experimental Study of the Microbial Induced Carbonate Precipitation (MICP) Effect on the Permeability of Carbonated Sands

Microbial induced carbonate precipitation (MCIP) is an environmentally and suitable method for soil remediation. In this method, urea is hydrolyzed by the urease enzyme, that is splashed from Sporosrcina Pasteurii bacteria. The calcium carbonate is formed in the presence of calcium ion. Calcium carbonate connects the soil particle like a bridge and improve its engineering characteristics. In the present research, the effect of MICP on the permeability of carbonated sand was investigated. The effect of factors such as concentration of the cementation solution, curing time and relative density on soil permeability have been studied. To consider the effect of different factors on the MICP performance, number of samples have been treated with MICP method and then constant head permeability test were conducted on the treated samples. the results show that as the concentration of cement solution was increased, the permeability of the samples was decreased. Loose Samples resulted in more decrease in permeability with respect to the dense samples. Also, bacterial activity was increased with time and after 14 days the variation in permeability was reduced. The highest rate of permeability reduction was around 60% for the sample prepared in loose state and cured with one molar concentration of cementation solution for 28 days