Volume 2, Issue 3 (September 1979)
A Laboratory Method of Measuring In-Situ Density Distribution in Dry Sand
Powerful numerical methods are widely available for the solution of most soil-structure interaction problems. Reported numerical models have been able to account for most of the complexities involved. In contrast, the techniques for obtaining realistic soil material properties for input data are few in number. To address this need, an indirect way of measuring the in-situ density of sand has been devised. The technique is based on the fact that changes in density cause changes in thermal conductivity of the sand. The details and construction of a thermal probe employing unsteady-state heat flow principles are described. The reliability of the technique developed has been found to be excellent for the sand used. Results obtained indicate that there is a direct relationship between the density and thermal conductivity values of the sand. Calibration charts and equations relating density and thermal conductivity of sand are presented. This technique is considered to be superior to existing methods for measuring in-situ density of sands. Possible applications of the technique are suggested.