Edward A. Nowatzki

Probabilistic analysis of collapsing soil by indicator kriging.

Collapsing soils, which undergo a large decrease in bulk volume virtually instantaneously upon saturation and/or load application, are found in arid and semi-arid regions of the world. In the western and midwestern U.S., problems resulting from collapsing soils are being recognized due to rapid industrial and urban developments. A probabilistic analysis of the distribution of such soils would be a rational approach for quantifying risk involved for a project in an area where such soils are found. Indicator kriging was applied to seven sets of collapse and collapse-related soil parameters to obtain the probability that a certain parameter is more or less than a predefined critical value for low, medium, and high collapse susceptibility. Results are presented in the form of probability contour plots with known variance of estimation of the probability. The ability to predict the probability of occurrence of collapse and collapse-related soil parameters for different critical values with a known degree of certainty is invaluable to planners, developers, and geotechnical engineers.

The effect of pneumatic tire characteristics on the performance of off-highway trucks

Abstract A mathematical model for pneumatic tire-soil interaction is used to evaluate the effect of pneumatic tire properties on the performance characteristics of a typical off-highway truck operating in sandy and clayey soil conditions. An example is given to demonstrate the good agreement between the results obtained from the mathematical model and information contained in the Caterpillar Performance Handbook.