ABSTRACT
A physical model involves a real object resting on or imbedded in a real material, not necessarily soil; the object is subjected to forces or displacements and the resulting displacements and stresses in object and material are measured and recorded. Among physical models in geotechnical engineering, certain tests have exhibited an historical popularity; somewhat surprisingly the tests continue to be performed. Perhaps simplicity of geometry, the existence of mathematical models, and ease of performance and measurements are the attractive features of such experiments. In the separate category of mathematical or numerical models, there are two groups that may be termed respectively single-element or constitutive models and multi-element or situation models. A sub-group of numerical models concerns computer simulation of granular media at the microscopic scale to gain understanding of the inter-grain mechanisms which lead to the constitutive response of soil. The author concludes that the scaling effect can be minimised by limiting the scaling factor to values down approximately 100g.
