Explaining the Hveem Stabilometer Test: Relating R-value, S-value, and the Elastic Modulus

The Hveem stabilometer is used by several states to obtain materials characteristics for designing pavements. This paper presents equations that relate the Hveem stabilometer R-value and S-value with the elastic modulus. It is shown that the elastic modulus is dependent on the following: the R- or S-value, the exudation pressure, the overconsolidation ratio, the Poisson's ratio, and the angle of internal friction of the material. It is also shown how the compaction pressure might affect the calculation if the material is time-dependent or viscoelastic. An example problem is provided to show how to calculate the elastic modulus using these pertinent factors. Typical laboratory test data are also presented to demonstrate the relationship between the R-value and the elastic modulus for three different highway soil materials. It is shown that the exudation pressure is indicative of the moisture content of the test samples. The R-value and elastic modulus are shown to be quite sensitive to the moisture content.