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

Rock Cutting: Atmospheric Conditions.
A: Tensile Failure vs. Shear Failure
0.0
-0.1
-0.2
-0.3
Tensile Failure
φ=00°
φ=05°
φ=10°
Ratio BTS/Cohesion
-0.4
-0.5
-0.6
Shear Failure
φ=15°
φ=20°
φ=25°
φ=30°
-0.7
φ=35°
-0.8
φ=40°
-0.9
φ=45°
-1.0
15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Blade Angle α (Degrees)
© S.A.M.
Figure 8-38: Below the lines (equation (8-125)) the cutting process is brittle
(shear failure); above the lines it is brittle (tensile failure).
A: Tensile Failure vs. Shear Failure
Tensile Failure
φ=00°
φ=05°
φ=10°
φ=15°
Ratio -UCS/BTS
10
Shear Failure
φ=20°
φ=25°
φ=30°
φ=35°
φ=40°
φ=45°
© S.A.M.
1
15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Blade Angle α (Degrees)
Figure 8-39: The ratio UCS/BTS, below the lines there is brittle
(shear failure), above the lines it is brittle (tensile failure).
Ductile
limit
Brittle
limit
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