Study of Solidification Technology of Marine Sludge by MICP Combined with Portland Cement

Abstract

AbstractGranite residual soil is widely distributed in South China, which often brings landslide and other geological disasters because of its obvious characteristics of water disintegration. Microbial Induced Calcite Precipitation (MICP) technology could improve the engineering properties of granite residual cemented-soil in the process of calcite precipitation. This study presents a laboratory tests to verify the process and to explore the influence of MICP technology on the mechanical properties of cement-soil such as strength and stress-strain relationship. Various technological factors such as cement mixing ratio (CMR), calcium ion concentration (CC) and calcium source (CS) were studied for the mechanical property improving of reinforced soil. Unconfined compressive strength (UCS) test was conducted to analyze the mechanical strength of cemented-soil strengthened by MICP. Based on these works, we have the following conclusions: (1) MICP technology can significantly enhance and improve the engineering properties such as strength, stiffness and toughness of cemented-soil; (2) Compared with the control group, the maximum growth rate of strength in the test group is 87.5%, and the most economical cement mixing ratio is about 15% (3) Calcium chloride and calcium acetate can improve the toughness of the sample, but the effect of calcium acetate is better, compared with the control group, the maximum growth rate of the toughness of the test group is up to 69.67%, when the calcium ion concentration is 0.5 mol/L.KeywordsGeotechnical engineeringBacillus pasteuriiMicrobial Induced Calcite Precipitation (MICP)Cement-soilMechanical properties