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

Saturated Sand Cutting.
6.13.2. Test Program.
Figure 6-48: A view of the measurement cabin.
The theory for the determination of the forces that occur during the cutting of fully water saturated sand with
straight blades is verified in two types of sand, sand with a d50 of 200 m and sand with a d50 of 105 m. The soil
mechanical parameters of these two types of sand can be found in 0 and 0
The research can be subdivided in a number of studies:
1. Research of the water resistance of the blades
2. Research of the accuracy of the assumed two-dimensional character of the cutting process on the middle blade
by changing the width of the middle blade with a total width of the middle blade and the side blades of 520
mm. This research is performed in the 200 m sand.
3. Research of the quantitative character of the side effects in relation to the size and the direction of the cutting
forces. This research is performed in the 200 m sand.
4. Research of the in the theory present scale rules. This research is performed in the 200 m sand.
5. Research of the accuracy of the theory of the cutting forces and the water sub-pressures in the non-cavitating
cutting process. This research is performed in the 200 m sand.
6. Research of the accuracy of the theory of the forces and the water sub-pressures in the non-cavitating and the
partly cavitating cutting process. This research is performed in the 105 m sand.
From points 4 and 5 it has also been established that the maximum pore percentage of the sand can be chosen for
the residual pore percentage. In the 200 m the dry critical density, the wet critical density and the minimal density
are determined, while in the 105 m sand the wet critical density and the minimal density are determined. These
pore values can be found in Appendix K and Appendix L
For both type of sand only the minimal density (maximum pore percentage n max) gives a large enough increase in
volume to explain the measured water sub-pressures. This is in contrast to Van Leussen and Nieuwenhuis (1984)
and Van Leussen and Van Os (1987 December), where for the residual density the wet critical density is chosen.
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