Theoretical soil mechanics and implement design

Abstract The fast few decades have seen the steady assimilation of developments in theoretical soil mechanics into the repertoire of analytical techniques for investigating complex soil-machine interactions. This paper attempts to review the contribution made by this knowledge in reinforcing the inherently empirical nature of tillage-implement design and development. The estimation of both quasi-static and dynamic tool forces, the evaluation of soil-disturbance patterns and problems of scouring and vibratory soil cutting have been approached from the point of view of classical soil-mechanics theory. The discussion also shows that the way tillage tools alter the physical environment of plant roots falls within the scope of critical-state soil mechanics and plant biomechanics. It has been shown that failing soil in tension is both a draught and energy-efficient form of loosening soil, and this points to new and challenging directions for the design and development of the next generation of primary-tillage implements.

[1]  P. L. Bransby,et al.  THE MECHANICS OF SOILS, AN INTRODUCTION TO CRITICAL STATE SOIL MECHANICS , 1987 .

[2]  Richard J. Godwin,et al.  The effect of time arrangement on soil forces and disturbance , 1984 .

[3]  W. C. Swick,et al.  A model for predicting dynamic soil tool interaction , 1985 .

[4]  Robert D. Grisso,et al.  A soil-tool model based on limit equilibrium analysis , 1983 .

[5]  D.R.P. Hettiaratchi,et al.  Theoretical mechanics of sub-surface cutting blades and buried anchors , 1980 .

[6]  Vasily Vasilevic Sokolovski,et al.  Statics of soil media , 1960 .

[7]  Richard J. Godwin,et al.  Soil Failure with Narrow Tines , 1977 .

[8]  William R. Gill,et al.  Soil dynamics in tillage and traction , 1967 .

[9]  D.R.P. Hettiaratchi,et al.  Stress-Deformation Behaviour of Soil in Root Growth Mechanics , 1973 .

[10]  A. J. Koolen.  Mechanical behaviour of soil by treatment with a curved blade having a small angle of approach , 1972 .

[11]  A. R. Reece,et al.  The calculation of passive soil resistance , 1974 .

[12]  P. C. Payne,et al.  The relationship between the mechanical properties of soil and the performance of simple cultivation implements , 1956 .

[13]  D.R.P. Hettiaratchi,et al.  The calculation of passive pressure in two-dimensional soil failure , 1966 .

[14]  J. R. O'callaghan,et al.  Structural mechanics of plant cells. , 1978, Journal of theoretical biology.

[15]  J. V. Stafford,et al.  The performance of a rigid tine in relation to soil properties and speed , 1979 .

[16]  D.R.P. Hettiaratchi,et al.  Mechanical behaviour of agricultural soils , 1980 .

[17]  Edward McKyes,et al.  The cutting of soil by narrow blades , 1977 .

[18]  K. Terzaghi.  Theoretical Soil Mechanics , 1943 .

[19]  J. R. O'Callaghan,et al.  The handling of soil by mouldboard ploughs , 1965 .

[20]  A. R. Reece,et al.  Symmetrical three-dimensional soil failure , 1967 .

[21]  Richard J. Godwin,et al.  The development and evaluation of a force prediction model for agricultural discs , 1985 .

[22]  A. R. Reece,et al.  Boundary Wedges in two-dimensional passive soil failure , 1975 .

[23]  R. T. Shield,et al.  STRESS AND VELOCITY FIELDS IN SOIL MECHANICS , 1954 .

[24]  D.R.P. Hettiaratchi,et al.  The mechanics of root growth in Granular media , 1969 .

[25]  Dr. Ir. Adrianus Jozef Koolen,et al.  Agricultural Soil Mechanics , 1983, Advanced Series in Agricultural Sciences.

[26]  J. R. O'callaghan,et al.  A membrane model of plant cell extension. , 1974, Journal of theoretical biology.

[27]  D. J. Olson,et al.  Effect of Speed on Soil Failure Patterns in Front of Model Tillage Tools , 1965 .

[28]  Alvin C. Bailey,et al.  The Effect of Geometric Parameters on Disk Forces , 1980 .

[29]  D.R.P. Hettiaratchi,et al.  The kinematics of sub-surface soil cutting blades , 1985 .

[30]  D.R.P. Hettiaratchi,et al.  A critical state soil mechanics model for agricultural soils , 1987 .

[31]  D. J. Schuring,et al.  Soil Deforming Processes and Dimensional Analysis , 1964 .

[32]  Alvin C. Bailey,et al.  The Influence of Harrow Disk Curvature on Forces , 1981 .

[33]  Edward McKyes,et al.  Soil Cutting and Tillage , 1986 .

[34]  S. S. Kofoed.  Kinematics and power requirement of oscillating tillage tools , 1969 .

[35]  Richard J. Godwin,et al.  An experimental investigation into the deep loosening of soil by rigid tines , 1978 .

[36]  James Graham.  Calculation of Passive Pressure in Sand , 1971 .