CONTRIBUTION TO THE MECHANICS OF RIGID WHEELS ON SAND
Abstract
Current theoretical concepts of soil-running gear interaction are based on empirical pressure-sinkage and shear stress-displacement relations. However, tests from which these relations were obtained present a poor analogy to the soil-running gear interaction. In particular, use of the shear stress- displacement relation for analytical evaluation of the shear stresses at the contact surface of rigid wheels on sand was found misleading, primarily because equations obtained by the bevameter or dragged plate tests describe soil behavior in an intermediate state between the elastic and plastic states. Recent publications show that part of the soil close to a powered wheel is in an actual plastic flow state and part is in a quasielastic state. Thus, the soil-bevameter interaction is fundamentally different than the soil-wheel interaction. Sela's theory of the relation between a rigid wheel and dry sand is based exclusively on the shear stress-displacement concept, and thus provided an excellent means of checking the concept. It uses the soil rupture pattern beneath rigid wheels on sand to subdivide the total interface into three zones of different soil behavior. This theory agrees better with test data than other theories.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1968
- Accession Number
- AD0833871
Entities
People
- Klaus W. Wiendieck