Wenner four-electrode method

Field measurement of soil resistivity using the Wenner four-electrode method... 

Direct shear test of soils under consolidated drained conditions pH of soil for use in corrosion testing Field measurement of soil resistivity using the Wenner four-electrode method Optimum S03 in portland cement... 

ASTM G 57-95A, Standard Test Method for Field Measurement ofSod Resistivity Using the Wenner Four-Electrode Method, ASTM International, West Conshohocken, PA, 1995. 

ASTM G57 (2001). Field Measurement of Soil Resistivity Using the Wenner Four-electrode Method American Society of Testing and Materials, West Conshohocken, PA. 

G57 Resistivity Using the Wenner Four-Electrode Method compared with results of similar experiments. 

As mentioned before, soil is a physically, chemically, and biologically complex system. Factors that affect corrosion in soil, in addition to specific ions, are resistivity of soil, oxygen content, and acidity. Field measurements of soil resistivity are covered in ASTM G 57, Method for Field Measurement of Soil Resistivity Using the Wenner Four-Electrode Method, which is the most widely used test, and using the proper meter produces accurate and reproducible results. Conducting field measurements of soil pH is covered in ASTM G 51, Test Method for pH of SoU for Use in Corrosion Testing. The corrosion resistance of lead and its alloys depends mainly upon the presence of silicate, carbonate, and to a lesser extent sulfates, in contributing to the passive film formation. 

The soil resistivity of the test site was measured by Wenner s four-electrode method. It was found that the test site was bilayered. The resistivity of the upper layer with a depth of 1.9 m was measured at 11.5 Qm, and that of the second layer, from a depth of 1.9 m to infinity, was 345 Qm. The steady-state resistance of a vertical grounding electrode with a length of 1 m was measured to be 9.4 Q by a Yokogawa resistivity meter, and that with the length of 1.5 m was 7.1 Q. 

Measurement of resistivity The most usual method of measuring soil resistivity is by the four-electrode Wenner method. Figure 10.48 indicates the basic circuit. The mean resistivity is given by... 

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