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

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

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<strong>The</strong> <strong>Delft</strong> <strong>Sand</strong>, <strong>Clay</strong> & <strong>Rock</strong> <strong>Cutting</strong> <strong>Model</strong>.<br />

Figure 9-6: <strong>The</strong> Crushed Type cutting mechanism. .............................................................................................300<br />

Figure 9-7: <strong>The</strong> forces on the layer cut in rock (hyperbaric). ...............................................................................301<br />

Figure 9-8: <strong>The</strong> forces on the blade in rock (hyperbaric). ....................................................................................301<br />

Figure 9-9: <strong>The</strong> horizontal cutting force coefficient λ HF for a 60 degree blade, h b/h i=1. .....................................303<br />

Figure 9-10: <strong>The</strong> vertical cutting force coefficient λ VF for a 60 degree blade, h b/h i=1. ........................................303<br />

Figure 9-11:<strong>The</strong> shear angle β, for a 60 degree blade, h b/h i=1. ............................................................................304<br />

Figure 9-12: <strong>The</strong> E sp/UCS ratio, for a 60 degree blade, h b/h i=1. ..........................................................................304<br />

Figure 9-13: <strong>The</strong> Tear Type cutting mechanism in rock under hyperbaric conditions. .......................................305<br />

Figure 9-14: <strong>The</strong> Chip Type cutting mechanism in rock under hyperbaric conditions. .......................................305<br />

Figure 9-15: <strong>The</strong> Curling Type or balling. ...........................................................................................................306<br />

Figure 9-16: <strong>The</strong> equilibrium of moments on the layer cut in hyperbaric rock. ...................................................306<br />

Figure 9-17: <strong>The</strong> ratio h b,m/h i for a 60 degree blade. ............................................................................................309<br />

Figure 9-18:<strong>The</strong> shear angle β for a 60 degree blade ...........................................................................................309<br />

Figure 9-19: <strong>The</strong> horizontal cutting force coefficient λ HC for a 60 degree blade. ................................................310<br />

Figure 9-20: <strong>The</strong> vertical cutting force coefficient λVC for a 60 degree blade. Positive downwards. ...................310<br />

Figure 9-21: <strong>The</strong> E sp/UCS ratio, for a 60 degree blade. .......................................................................................311<br />

Figure 9-22: <strong>The</strong> theory of hyperbaric cutting versus the Zijsling (1987) experiments. .....................................313<br />

Figure 9-23: <strong>The</strong> specific energy E sp and the drilling strength S, theory versus the Zijsling (1987) experiments.<br />

.......................................................................................................................................................314<br />

Figure 9-24: <strong>The</strong> ratio h b,m/h i for a 110 degree blade. ..........................................................................................315<br />

Figure 9-25:<strong>The</strong> shear angle β for a 110 degree blade. ........................................................................................315<br />

Figure 9-26: <strong>The</strong> horizontal cutting force coefficient λ HC for a 110 degree blade. ..............................................316<br />

Figure 9-27: <strong>The</strong> vertical cutting force coefficient λVC for a 110 degree blade. Positive upwards. ......................316<br />

Figure 9-28: <strong>The</strong> E sp/UCS ratio, for a 110 degree blade. .....................................................................................317<br />

Figure 9-29: <strong>The</strong> specific energy E sp in rock versus the compressive strength (UCS) for a 110º blade...............319<br />

Figure 9-30: <strong>The</strong> specific energy E sp in rock versus the compressive strength (UCS) for a 45º blade. ...............320<br />

Figure 9-31: <strong>The</strong> specific energy E sp in rock versus the compressive strength (UCS) for a 60º blade. ...............321<br />

Figure 10-1: <strong>The</strong> occurrence of a wedge. .............................................................................................................325<br />

Figure 10-2: <strong>The</strong> forces on the layer cut when a wedge is present.......................................................................329<br />

Figure 10-3: <strong>The</strong> forces on the wedge. .................................................................................................................329<br />

Figure 10-4: <strong>The</strong> forces on the blade when a wedge is present. ...........................................................................330<br />

Figure 10-5: <strong>The</strong> moments on the wedge. ............................................................................................................330<br />

Figure 11-1: Definitions. ......................................................................................................................................333<br />

Figure 11-2: Alternative geometry of the layer cut. ............................................................................................333<br />

Figure 11-3: <strong>The</strong> cutting mechanism. ..................................................................................................................333<br />

Figure 11-4: <strong>The</strong> forces on the layer cut when a wedge is present.......................................................................336<br />

Figure 11-5: <strong>The</strong> forces on the wedge. .................................................................................................................337<br />

Figure 11-6: <strong>The</strong> forces on the blade when a wedge is present. ...........................................................................337<br />

Figure 11-7: <strong>The</strong> moments on the wedge. ............................................................................................................338<br />

Figure 11-8: <strong>The</strong> shear angle, wedge angle and mobilized external friction angle calculated with wedge. .........339<br />

Figure 11-9: <strong>The</strong> total cutting force. ....................................................................................................................340<br />

Figure 11-10: <strong>The</strong> direction of the total cutting force. .........................................................................................340<br />

Figure 11-11: <strong>The</strong> shear angle of Hatamura & Chijiiwa (1977B) versus the calculated shear angles, with and<br />

without wedge. ..............................................................................................................................341<br />

Figure 11-12: <strong>The</strong> shear angle, wedge angle and mobilized external friction angle calculated with wedge. .......341<br />

Figure 11-13: <strong>The</strong> total force of Hatamura & Chijiiwa (1977B) versus the calculated total force, with and without<br />

wedge. ...........................................................................................................................................342<br />

Figure 11-14: <strong>The</strong> direction of the cutting force of Hatamura & Chijiiwa (1977B) versus the calculated force<br />

direction, with and without wedge. ...............................................................................................342<br />

Figure 12-1: Failure pattern with rake angle of 120º. ...........................................................................................345<br />

Figure 12-2: <strong>Sand</strong> cutting with a wedge, definitions. ...........................................................................................346<br />

Figure 12-3: <strong>The</strong> cutting mechanism. ..................................................................................................................346<br />

Figure 12-4: <strong>The</strong> forces on the layer cut in saturated sand with a wedge. ...........................................................348<br />

Figure 12-5: <strong>The</strong> forces on the wedge in saturated sand. .....................................................................................348<br />

Figure 12-6: <strong>The</strong> forces on the blade in saturated sand with a wedge. .................................................................348<br />

Figure 12-7: <strong>The</strong> volume balance over the shear zone. ........................................................................................351<br />

Figure 12-8: Possible flow lines. ..........................................................................................................................351<br />

Figure 12-9: <strong>The</strong> boundaries of the FEM model. .................................................................................................352<br />

Figure 12-10: Pore pressure distribution on the shear plane A-B, the bottom of the wedge A-D, the blade D-C and<br />

the front of the wedge A-C. ...........................................................................................................352<br />

Page 440 of 454 TOC Copyright © Dr.ir. S.A. Miedema

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