SACL Engineers developed a state-of-the-art piston flume for erodibility testing.  Soil samples can be extracted from Shelby tubes directly into the flume’s piston sample tube and tested for critical shear and erodibility with metered flows up to 6 m/s.  The fluid shear imparted on the soil surface is measured directly at a rate of 10 readings per second.  A computer-controlled actuator is used to maintain the soil surface flush with the base of the flume which allows for measuring the erosion rate corresponding to the measured flow velocity.