Nonlinear wall pressure of a plunged granular column

Scalings for slow drag and wall pressures in a plunged granular column are experimentally studied. A granular column is prepared in a cylindrical container and a spherical intruder is slowly plunged into it. Quasistatic drag force and pressures at the bottom and the side wall are measured simultaneously. Using the experimental data, we find scaling laws for drag force and wall pressures with some relevant length scales such as grains size and column dimensions. The obtained scaling laws elucidate the origin of nonlinear behavior of granular pressure. That is, the dimensionless column thickness is a key parameter to characterize the nonlinear granular pressure transmission.