The Delft Sand, Clay & Rock Cutting Model, 2019a

Saturated Sand Cutting.
The tests are carried out using a middle blade, flanked on both sides by a side blade, in order to establish a twodimensional
cutting process on the middle blade. The middle blade (center blade) is mounted on a dynamometer,
with which the following loads can be measured:
1. The horizontal force
2. The vertical force
3. The transverse force
4. The bending moment
The side blades are mounted in a fork-like construction, attached to some dynamometers, with which the following
loads can be measured:
1. The horizontal force
2. The vertical force
Figure 6-41 and Figure 6-42 show the mounting construction of the blades.
Figure 6-39: An overview of the new laboratory DE.
In the middle blade, four pore pressure transducers are mounted, with which the pore pressure distribution on the
blade can be measured. However no tests are performed in which the forces on the side blades and the pore
pressures are measured at the same time. The measuring signals of the dynamometers and the pressure transducers
are transmitted to a measurement compartment through pre-amplifiers on the main carriage. In this measurement
compartment the measuring signals are suited by 12 bit, 400 Hz A/D converters for processing on a P.C. (personal
computer), after which the signals are stored on a flexible disk. Next to the blades, under water, an underwater
video camera is mounted to record the cutting process. This also gives a good impression of the shear angles
occurring.
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