Abstract
In most geotechnical texts and courses, uncertainty is relegated to a minor position, and the bulk of the text/course is evaluated in a traditional deterministic fashion. However, in not attempting to embrace the uncertainties directly, one is just avoiding the truth and minimizing the problem. As a necessary step to alleviate this problem, this paper focuses an the typical inherent variabilities for the basic properties of natural geomaterials. The issue of measurement error, which is closely related, is noted when necessary. The results of an extensive literature review on inherent variability are presented. This variability is modeled as a random field, which can be described concisely by the coefficient of variation (COV) and the scale of fluctuation. The COV of inherent variability for various test measurements is given in histograms to illustrate its population distribution. The means and standard deviations of the COV are shown with the total number of data groups, and the shapes of the histograms are discussed. The scale of fluctuation is discussed elsewhere.