Gomez, Michael MOliveira Ribeiro, Bruna Gabrielly2026-04-202026-04-202026OliveiraRibeiro_washington_0250E_29308.pdfhttps://hdl.handle.net/1773/55467Thesis (Ph.D.)--University of Washington, 2026Microbially Induced Calcite Precipitation (MICP) is a bio-mediated technology that can improve the engineering properties of granular soils through the generation of calcium carbonate minerals on soil particles surfaces and at interparticle contacts. The process can offer an environmentally beneficial alternative to conventional ground improvement methods, which have traditionally relied on energy-intensive interventions. Through nearly two decades of research, a wide array of geotechnical applications for this process have been explored ranging from liquefaction mitigation to surficial soil stabilization. While promising, there has remained limited understanding of the permanence of the generated carbonate minerals and how the engineering behaviors of biocemented soils may change over time following chemical and mechanical damage. In this research, the life-cycle performance of biocementation is investigated through experiments examining the long-term geochemical permanence of biocementation and the engineering behavior of biocemented soils following chemically induced damage. First, batch and soil column experiments were performed wherein soils were first biocemented and then subjected to acidic solutions to induce dissolution. Insights from these experiments were then used to calibrate and validate a reactive transport model capable of forward predicting calcium carbonate dissolution spatially and temporally for a variety of different geochemical conditions. Next, direct simple shear tests were employed to examine the consequences of chemical damage on the engineering behaviors of biocemented loose sands and identify new methods by which post-treatment material damage might be detected and accounted for. Results from this research will significantly improve our understanding of the long-term engineering performance of biocementation soil improvement including site-specific material longevity, changes in engineering behaviors following damage, life cycle environmental impacts, and favorable uses cases for the technology that maximize environmental benefits.application/pdfen-USnoneBiocementationGeotechnical EngineeringLaboratory TestingLiquefactionMICPSoil ImprovementCivil engineeringGeotechnologyGeological engineeringCivil engineeringThesis