Mitigation of liquefaction using biogas desaturation

One method for mitigation of liquefaction is biogas desaturation, that is, to use gas generated biologically to make fully saturated sand slightly unsaturated. In this paper, the effectiveness of this method is evaluated using model tests. The biogas desaturation method generates tiny inert gas bubbles within liquefaction prone zone to increase the soil resistance to liquefaction. Results of models have shown that as the degree of saturation of the soil is controlled to be less than 90%, the generation of pore pressure in sand during cyclic loading is largely contained. Suggestions for the practical implementation of this method are also made. Methods to enhance the stability of the gas bubbles are also discussed.