[4] Several mechanisms have been identified by which bacteria can induce the calcium carbonate precipitation, including urea hydrolysis, denitrification, sulfate production, and iron reduction.
[7] Several applications of this process have been proposed, such as remediation of cracks and corrosion prevention in concrete,[8][9][10][11][12][13][14][15][16] biogrout,[17][18][19][20][21][22][23][24] sequestration of radionuclides and heavy metals.
[31] Two separate and often concurrent heterotrophic pathways that lead to calcium carbonate precipitation may occur, including active and passive carbonatogenesis.
MICP has been reported as a long-term remediation technique that has been exhibited high potential for crack cementation of various structural formations such as granite and concrete.
[40][41] Architect Ginger Krieg Dosier won the 2010 Metropolis Next Generation Design Competition for her work using microbial-induced calcite precipitation to manufacture bricks while lowering carbon dioxide emissions.
[43] Microbial induced calcium carbonate precipitation has been proposed as an alternative cementation technique to improve the properties of potentially liquefiable sand.
[24] Light microscopic imaging suggested that the mechanical strength enhancement of cemented sandy material is caused mostly due to point-to-point contacts of calcium carbonate crystals and adjacent sand grains.
[46] One-dimensional column experiments allowed the monitoring of treatment progration by the means of change in pore fluid chemistry.
[1][18][24][47] Triaxial compression tests on untreated and bio-cemented Ottawa sand have shown an increase in shear strength by a factor of 1.8.
[23] Originally MICP was tested and designed for underground applications in water saturated ground, requiring injection and production pumps.
These synthetic additives are typically costly and can create environmental hazards by modifying the pH and contaminating soils and groundwater.
Based on the size of microorganism, the applicability of biocementation is limited to GW, GP, SW, SP, ML, and organic soils.
In clayey soil, bacteria are capable of reorienting and moving clay particles under low confining stress (at shallow depths).
Similarly, at larger depths, silt and sand particles may crush and cause a reduction in pore spaces, reducing the biological activity.