Measurement and modelling of soil displacement from sweeps with different cutting widths

Abstract

Soil dynamic properties are important performance indicators for soil-engaging tools. In this study, soil displacement and cutting forces of selected sweeps were measured and simulated. The sweeps had different cutting widths: 153, 280, and 330 mm, and they were tested in an indoor soil bin with a sandy loam soil at a working depth of 50 mm and a travel speed of 1.53 m s−1. A discrete element model was developed using PFC3D (Particle Flow Code in Three Dimensions) to simulate soil-sweep interactions. With the measured soil cutting forces, the model particle stiffness was calibrated to be 3 × 103 N m−1. Results from modelling and measurements showed a general trend of the highest displacements around the centre of the path of sweep, reducing at the further distance away from the centre. Among all directions, measured soil displacements were the highest in the forward direction, up to 608 mm. Measured results showed that forward soil displacements were smaller for smaller sweeps, and lateral soil displacements were lower at a greater depth regardless of the sweeps. Simulated forward and lateral displacements did not contradict these results. Among all the sweeps, the 153-mm wide sweep had significantly higher vertical displacements at all depths as compared to the other sweeps, demonstrated by both measurements and simulations. Overall, the simulated soil displacements were lower than the measured values in all three directions. The accuracy of the model needs to be improved for predictions of soil displacements.