Visual experimental study on development of mud film in slurry shield excavation face based on transparent soil technology

In order to solve the problems of grouting diffusion and invisible formation process in shield slurry film forming test, transparent soil and transparent slurry were introduced to carry out shield mud film test based on shield grouting model. Using laser imaging combined with CCD camera (high-speed industrial camera) rapid capture photography technology, through a series of visible physical model tests of slurry diffusion and mud film development under different working conditions, the temporal and spatial conditions of slurry diffusion were observed and recorded in real time to explore the slurry diffusion law and the formation mechanism of mud film in slurry shield excavation face.The phenomenon shows that the smaller the grouting pressure is, the more favorable the formation of mud film is.The mud penetration distance is generally proportional to the grouting pressure.The infiltration distance of the grout increases with time, and the infiltration distance of the grout is similar at each moment under the same grouting pressure. The leachate volume and time show a quadratic function roughly under the same density and mud pressure, and the increase rate of the leachate volume begins to slow down with time.