Determination of the correlation between the electrical resistivity of non-cohesive soils and the degree of compaction
Résumé
Electrical resistivity measurements provide potentially powerful tool for estimation of physical parameters of soils and materials used in earthworks and constructions like embankments and dams. The study demonstrates the correlation between the resistivity of non-cohesive soils and the degree of compaction, which is an indicator of important and possibly risks bearing hydraulic piping or tunneling. In this paper we investigate the relationship between electrical resistivity of non-cohesive soils and granulated materials used in earth-works and constructions such as road embankments, and degree of compaction. Laboratory analyses of the last parameter are time consuming and estimated using parameters such as moisture content, bulk density and porosity, the same parameters (mostly obviously porosity and moisture content and including pore water mineralization) determine electrical resistivity. In consequence, electrical resistivity is a potentially well adapted alternative method for determination of the degree of compaction. To investigate the problem, electrical resistivity survey was conducted in a laboratory using soil samples representing fine, medium and coarse sands, submitted to successive steps of compaction. The measurements were carried out in the box, which may be compared with the construction such as an embankment. Obtained resistivity values were analyzed taking into consideration electrode spacing and the physical parameters of soil at each step of compaction.