The Cutting of Water Saturated Sand at Large Cutting Angles

In the last decennia extensive research has been carried out into the cutting of water saturated sand. In the cutting of water-saturated sand, the phenomenon of dilatation plays an important role. In fact the effects of gravity, inertia, cohesion and adhesion can be neglected at cutting speeds in the range of 0.5 – 10 m/s. In the cutting equations, as published by Miedema, there is a division by the sine of the sum of the blade angle, the shear angle, the angle of internal friction and the soil/interface friction angle. When the sum of these angle approaches 180°, a division by zero is the result, resulting in infinite cutting forces. There are 3 possible conditions that can be used: the principle of minimum energy, the circle of Mohr, and the equilibrium of moments of the wedge. These methods are discussed and the choice made is explained.