Agitating tests of fluid soil admixed with foam in the chamber of EPB shield

The visualization system of soil fluidity in the chamber EPB (Earth Pressure Balanced) shield has been developed to maintain appropriate excavated real time during advance under tunnel construction. For further improvement system, agitation tests fluid admixed with foam have carried out study relationship between number rotations and agitating torque soil. It is confirmed by that sand reduces increasing range small rotations, slightly increases large rotations. phenomena appeared strongly as volume percentage addition decreased. On other hand, case weight fine friction soil, reduced torque, however, increased increased. considered are affected particles fluidization due fraction