2020 Volume 76 Issue 2 Pages I_750-I_755
Terrestrial soil excavated during construction is expected to be utilized as environmental improvement materials in marine area. However, it is a problem that soil generated by shield tunnel excavation often contains surfactants. With focusing on polyoxyethylene alkyl ether surface (AES), which is a typical main component in the surfactants, we considered the experimental methods to assess the natural degradation of AES in soil and the adsorption to soil. As the results regarding the degradability experiment, the following points to note were suggested to be considered: keeping the moisture content of the soil to the liquid limit; the shaking operation is performed in a dark place at 5 °C; shaking the soil in water at least for two hours, etc. Regarding the adsorption experiment, the following points were needed to be considered; a stirrer-type operation is applicable instead of shaking-type operation for the stirring processing; the solid-liquid ratio is appropriate 1:50 for black clayey soil.
