Chapter 4 - Characterization of the Response of Terrains to Normal and Repetitive Loadings

Abstract

This chapter describes the measurement and characterization of the response of a variety of terrains, including mineral terrain, muskeg, and snow-covered terrain. One of the fundamental tasks in the characterization of terrain behavior is to establish functional relationships that can realistically describe the responses of the terrain to various types of loading, such as the stress–strain relationship, pressure–sinkage relationship, and shear stress–shear displacement relationship. The responses of a variety of mineral terrains in Eastern Ontario, Canada, including sand (LETE sand), sandy loam, clayey loam, and loam to normal and repetitive loadings were measured and characterized. The results indicate that there is little difference between the values of the pressure–sinkage parameters obtained using a set of rectangular plates of large aspect ratios and those obtained with a set of circular plates having radii equal to the widths of the rectangular plates. The responses of two muskegs in the Petawawa area, Ontario, Canada, to normal load and to repetitive loading were measured using the bevameter together with the automatic data acquisition and processing system. A well-defined critical pressure at which the surface mat of the muskeg is broken can be identified.