Abstract: With the increased use of agricultural machinery in field operations, soil compaction has become increasingly severe, and the plough pan has become deeper. Subsoiling is an excellent way to address this problem. However, it is limited by high energy consumption, which is closely related to tillage force. To investigate the effect of the geometric shape of shanks and tines on tillage force and soil disturbance in loam, a layered soil model in accordance with the actual conditions was established and five different subsoilers were simulated via discrete element modeling. The results indicated that the shank impacted soil disturbance and tine impacted tillage force. The draft force of curved shank and chisel tine was 8% less than that of the straight shank and sweep tine. The straight shank and sweep tine produced a larger furrow profile and a higher furrow width. The subsoiler with curved shank and chisel tine (C-C) exhibited the lowest specific resistance (12.87, 17.52, 19.46 and 21.18 kN/m² in the 30, 35, 40 and 45 cm tillage depth, respectively) considering the draft force and soil disturbance characteristics. Hence, these results will facilitate in the selection of a suitable subsoiler and design of new subsoilers with lower energy consumption requirements for loam areas worldwide.

The full text can be downloaded at https://link.springer.com/article/10.1007/s40436-020-00318-x

Key words: Subsoiler, Discrete element method (DEM), Tillage force, Soil disturbance, Soil compaction