Cranfield University

List of Figures and Tables
Figure 33: Soil displacement for different undercarriage systems................................. 43
Figure 34: Group of wheel type soil displacement......................................................... 44
Figure 35: Group of track type soil displacement .......................................................... 44
Figure 36: Penetrometer resistance vs. depth for the Claas unit at three belt pressures. 49
Figure 37: Soil displacement vs. depth for the Claas unit at three belt pressures .......... 50
Figure 38: Pressure trace in soil below different belt pressures of Claas unit ............... 50
Figure 39: Pressure summary for different belt tensions ............................................... 51
Figure 40: Track units; TerraTrac, Westtrack, SPT, and Stocks.................................... 52
Figure 41: Penetrometer resistance vs. depth for different track units........................... 53
Figure 42: Soil displacement vs. depth for different track units .................................... 54
Figure 43: Pressure profiles for track units including a 800/10.5/2.5 for reference....... 55
Figure 44: Rectangularity for different track units......................................................... 56
Figure 45: Pressure summary for different track units................................................... 56
Figure 46: Soil displacement vs. depth for implement tyres and the track at 12 t ......... 58
Figure 47: Soil displacement vs. depth for 900/5/0.5..................................................... 59
Figure 48: Soil displacement vs. depth on clay soil for individual treatments .............. 62
Figure 49: Soil displacement and regression lines for clay with individual groups....... 63
Figure 50: Soil displacement and regression lines for clay with pooled groups............ 64
Figure 51: Soil displacement and regression lines for sandy loam subsoiled ................ 65
Figure 52: Soil displacement and regression lines for sandy loam shallow tilled ......... 66
Figure 53: Penetrometer resistance for the controls on the clay side............................. 68
Figure 54: Penetrometer resistance for clay control and the passage............................. 69
Figure 55: Penetrometer resistance for the controls on the sandy loam shallow tilled .. 70
Figure 56: Penetrometer resistance for sandy loam control and the passage................. 70
Figure 57: Penetrometer resistance for the controls and the passage............................. 71
Figure 58: Penetrometer resistance for control and the passage .................................... 71
Figure 59: Penetrometer resistance diagram after a tracked and a wheeled machine .... 72
Figure 60: Rut depths on sandy loam soil ...................................................................... 73
Figure 61: Ruts depths on sandy loam soil from further above ..................................... 73
Figure 62: Gamma ray dry bulk density......................................................................... 79
Figure 63: Draught force vs. depth for a subsoiler tine.................................................. 84
Figure 64: Draught force for subsoiling on the clay soil................................................ 88
Figure 65: Draught force for subsoiling on the sandy soil ............................................. 88
Figure 66: Estimated pressure from O’Sullivan et al. (1998) vs. contact pressure...... 100
Ph.D. Thesis Dirk Ansorge (2007)
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