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5.1: Introduction

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    Screen Shot 2020-08-17 at 1.29.10 PM.png
    Figure 5-1: The cutting mechanism in dry sand, the Shear Type.
    Screen Shot 2020-08-17 at 1.41.59 PM.png
    Figure 5-2: Dry sand modeled according to the Flow Type.

    In literature most cutting theories are based on one time failure of the sand. Here a continuous cutting process is considered. In dry sand the cutting processes are governed by gravity and by inertial forces. Pore pressure forces, cohesion and adhesion are not present or can be neglected. Internal and external friction are present. The cutting process is of the Shear Type with discrete shear planes (see Figure 5-1), but this can be modeled as the Flow Type (see Figure 5-2), according to Merchant (1944). This approach will give an estimate of the maximum cutting forces. The average cutting forces may be 30%-50% of the maximum cutting forces.

    This page titled 5.1: Introduction is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Sape A. Miedema (TU Delft Open Textbooks) via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.