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Appendix the evaluation of the behaviour of the model with respect to the slope of the recompression line (RCL) which determines soil behaviour at the beginning of reloading (the second cycle in a loading-unloading sequence). The smaller the slope of the RCL the faster soil compacts in the consecutive loading cycles and has undergone less strengthening than one with a larger RCL slope. As the close agreement between measured and predicted data shows, the model predicts the soil behaviour correctly for subsequent passes without the necessity to adjust the RCL. The slope of the RCL = 0.0327 as defined by O’Sullivan (1998) can be maintained for this sandy loam, too. In general a close agreement at the surface is achieved and only displacement behaviour at depth differs slightly when the displacement approaches zero anyway and the deviation is still within the error of measurement. Depth (mm) 0 100 200 300 400 500 600 700 800 Deformation (mm) -20 0 20 40 60 80 100 120 140 10.5 t Multipass Measured 10.5 t Multipass Predicted 5 t Multipass Measured 5 t Multipass Predicted Figure 14: Predicted and measured soil displacement after multipasses of a 900 mm tyre 11.1.3.4 Passes with complete vehicles Figure 15 shows the predicted soil displacement below vehicles after the pass of the front and the rear axle. In general a close agreement was obtained between measured and predicted soil displacement. A close agreement was found for both the 900/10.5/1.9 followed by the 500- 70/4.5/2.3 (900-500) and the 590/4/1.2 followed by the 290/1.5/2 (590-290). For the 900/10.5/1.9 followed by the 700/10.5/1.0 (900-700) combination rut depth prediction was significantly smaller than the measured value, but the slope was similar. The 680/10.5/2.2 followed by the 500-85/4.5/1.4 (680-585) had closer agreement with respect to the predicted rut depth, but overall the slope differed more. Ph.D. Thesis Dirk Ansorge (2007) 213
Appendix To summarize the ability to predict soil displacement after multiple passes from either a three front axle pass or whole machines the slope of the measured and predicted soil displacement lines were calculated and plotted against each other in Figure 16. The agreement between measured and predicted soil displacement is high. The average increase in DBD was predicted to within +/- 1.5 % for all treatments except the 680-585 with +3%. The slope shows that the increase is underpredicted by 5 % compared to the 1:1 line with an R 2 of 0.85. Depth (mm) Depth (mm) 0 100 200 300 400 500 600 700 800 0 100 200 300 400 500 600 700 800 Dis placement (m m) 0 20 40 60 80 100 120 Displacement (mm) 900-700 0 20 40 60 80 100 120 140 Depth (mm) 0 20 40 60 80 100 120 0 100 200 300 400 500 600 700 800 Depth (mm) Displacement (mm) -10 0 10 20 30 40 50 60 70 80 90 0 Ph.D. Thesis Dirk Ansorge (2007) 100 200 300 400 500 600 700 800 900-500 Displacement (mm) 680-585 590-290 Figure 15: Predicted (♦) and measured (■) soil displacement on stratified soil Predicted Increase (%) 30 25 20 15 10 5 0 conditions after the pass of a combine harvester with different tyre and load combinations. The least significant difference (LSD) at 95 % is also shown y = 0,9467x R 2 = 0,8863 0 5 10 15 20 25 30 Measured Increase (%) Figure 16: Predicted vs. measured increase in soil displacement for multi passes from whole machines or front axles. Also shown is the 1:1 relationship (broken line) 214
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Cranfield University School of Appl
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Abstract Ancillary experiments show
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Table of Contents TABLE OF CONTENTS
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Table of Contents 4.1.3 Analysis of
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Table of Contents 11.1.1.1 Comparis
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List of Figures and Tables Figure 3
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List of Figures and Tables Figure 1
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Nomenclature NOMENCLATURE Abbreviat
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Introduction 1 INTRODUCTION 1.1 Bac
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Introduction � Ansorge, D. and Go
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Introduction 1.2 Aim To elucidate t
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Introduction a) the soil compaction
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Experimental Methods 2.1.1.1 Test F
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Experimental Methods had been mount
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Experimental Methods track; the loa
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Experimental Methods 800/10.5/2.5 t
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Experimental Methods term. In the m
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Experimental Methods Soil Surface F
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Experimental Methods Depth (cm) 0 1
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Experimental Methods ence surface c
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Experimental Methods chine derives
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Experimental Methods depth. The dat
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Experimental Methods with water and
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Experimental Methods 2.4 Statistica
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Laboratory Studies Into Undercarria
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Field Study With Full Size Combine
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Alleviation of Soil Compaction Howe
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Alleviation of Soil Compaction not
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Alleviation of Soil Compaction in a
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Alleviation of Soil Compaction diff
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Soil Compaction Models sibilities t
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Soil Compaction Models depends on t
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Soil Compaction Models Wroth (1968)
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Soil Compaction Models however, the
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Soil Compaction Models level. Criti
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Soil Compaction Models Utilizing Ke
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Soil Compaction Models average of m
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Soil Compaction Models Depth (mm) -
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Soil Compaction Models ture content
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Soil Compaction Models with four ot
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Soil Compaction Models Predicted In
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Soil Compaction Models Depth (mm) -
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Soil Compaction Models and 13.7 % b
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Soil Compaction Models Rel. Density
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Soil Compaction Models VCL paramete
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Soil Compaction Models The approach
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Soil Compaction Models surface stay
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Soil Compaction Models This result
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Soil Compaction Models 6.6.1.3 Wate
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Soil Compaction Models σσ 1 (kPA)
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Soil Compaction Models pressure to
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Soil Compaction Models The response
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Soil Compaction Models On medium so
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Soil Compaction Models SOILFLEX tak
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Ancillary Experiments 7 ANCILLARY E
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Ancillary Experiments Average conta
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Ancillary Experiments In order to c
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Ancillary Experiments contrary, the
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Ancillary Experiments Figure 102: S
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Ancillary Experiments track and the
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Ancillary Experiments even when hav
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Ancillary Experiments 7.3.2 Influen
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Ancillary Experiments The results f
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Ancillary Experiments Figure 117: S
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Ancillary Experiments Contact Press
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Ancillary Experiments Figure 123: F
Page 179 and 180: Ancillary Experiments Sinkage (mm)
Page 181 and 182: Ancillary Experiments model which o
Page 183 and 184: Ancillary Experiments 7.3.5 The Inf
Page 185 and 186: Ancillary Experiments 7.3.7 Discuss
Page 187 and 188: Ancillary Experiments Terzaghi (194
Page 189 and 190: Ancillary Experiments contact area.
Page 191 and 192: Ancillary Experiments soil forward
Page 193 and 194: Conclusions � The longitudinal so
Page 195 and 196: Bibliography 10 BIBLIOGRAPHY Aboaba
Page 197 and 198: Bibliography Defossez, P., Richard,
Page 199 and 200: Bibliography Gregory, A.S.; Whalley
Page 201 and 202: Bibliography Lamande, M., Schjonnin
Page 203 and 204: Bibliography Seig, D., 1985. Soil C
Page 205 and 206: Appendix 11 APPENDIX Ph.D. Thesis D
Page 207 and 208: Appendix Figure 32: VCL sample at t
Page 209 and 210: Appendix comparison at the deepest
Page 211 and 212: Appendix Estimated Pressure (kPa) 2
Page 213 and 214: Appendix 11.1.1.2.1 SOCOMO One of t
Page 215 and 216: Appendix by Seig (1985) who showed
Page 217 and 218: Appendix Soil water content 15 % an
Page 219 and 220: Appendix Adapting critical state so
Page 221 and 222: Appendix density is obtained by add
Page 223 and 224: Appendix Table 5: Values of constan
Page 225 and 226: Appendix choice of a concentration
Page 227 and 228: Appendix 11.1.3.1 Dense/Hard and Lo
Page 229: Appendix 11.1.3.2 Stratified Soil C
Page 233 and 234: Appendix In the following the predi
Page 235 and 236: Appendix concentration factor of 4,
Page 237 and 238: Appendix 11.1.5.1 Confining Pressur
Page 239 and 240: Appendix Figure 24. The VCL created
Page 241 and 242: Appendix Rel. Density 2 1,9 1,8 1,7
Page 243 and 244: Appendix relation of � 1 to � 2
Page 245 and 246: Appendix Rel. Density 2 1,9 1,8 1,7
Page 247 and 248: Appendix Rel. Density 1,7 1,68 1,66
Page 249 and 250: Appendix Depth (mm) 0,0 100,0 200,0
Page 251 and 252: Appendix Figure 42: Plate in cookin
Page 253 and 254: Appendix � z � � �� k c p
Page 255 and 256: Appendix Table 8: n and k depending
Page 257 and 258: Appendix to the plate sinkage equat
Page 259 and 260: Appendix with a slight deviation fr
Page 261: Appendix Table 12: DBD values for a
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