Mechanical properties of biocement formed by microbially induced carbonate precipitation

• Published in: Acta geotechnica Vol. 17; no. 11; pp. 4905 - 4919
• Main Authors: Ma, Guoliang, Xiao, Yang, Fan, Wenjun, Chu, Jian, Liu, Hanlong
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-11-2022; Springer Nature B.V
• Subjects: Bacteria; Carbonates; Cement; Cementation; Chemical precipitation; Civil engineering; Complex Fluids and Microfluidics; Constitutive models; Engineering; Foundations; Geoengineering; Geotechnical Engineering & Applied Earth Sciences; Hydraulics; Investigations; Mechanical properties; Methods; Precipitates; Research Paper; Sand; Sand & gravel; Soft and Granular Matter; Soil Science & Conservation; Solid Mechanics; Stabilizing; Tensile strength; X-ray diffractometry (XRD); Scanning electron microscope (SEM); Microbially induced carbonate precipitation (MICP); Brazil splitting tensile strength; Biocement; Mercury intrusion porosimetry (MIP)
• ISSN: 1861-1125; 1861-1133
• DOI: 10.1007/s11440-022-01584-8

The failure of biocemented sand can be attributed to the breakage of biocement and the exfoliation of precipitates from sand surfaces. Therefore, optimizing the mechanical properties of the biocement is one of the methods to improve the performance of MICP for stabilizing sand. Besides, a deep understanding of the properties of biocement is necessary for simulating and establishing constitutive models to predict the mechanical properties of biocemented sand. In this paper, Brazil splitting tensile strength tests were conducted on the biocement formed under different concentrations of cementation solutions, volume ratios of bacterial solutions to cementation solutions, temperature, and bacterial suspension types. The above factors cannot only affect the distribution of precipitates both at the microscale and macroscale, which were always regarded as the main reason for the different strength of biocemented sand earlier, but also affect the physical–mechanical properties of biocement, which was the contribution of the current work.