Iron-based bio-grout for soil improvement and land reclamation

Chemical grouts have often been used in geotechnical applications. However, they are expensive, usually toxic, and may be harmful to the environment. A new type of grout, biogrout, which is based on ferrous/ferric salts, has been developed using microbial technology. The time for the biogrout to take effect and the extent that biogrouts penetrate the soil depend on the concentration and activity of specific bacteria in the biogrout. The reaction time varies from several minutes to several days. Testing results show that ferrous/ferric-based biogrouts are applicable for construction of reservoirs, ponds, dams, and land reclamation. The biogrout also increases the strength and decreases the permeability of the soil. Geotechnical applications of the biogrout could be; 1) formation of grout curtains; 2) diminishing piping of earth dams and dikes; 3) construction of reservoirs and ponds; 4) seepage control; 5) fixation of the leakages of ground water in underground constructions; 6) reduction of pipeline corrosion; 7) land reclamation; 8) sealing of tunnel seepage; 9) the reduction of soil liquefaction.