Soil resistivity measurement

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Soil resistivity measurement [Copy link]

Are there any seniors in geotechnical engineering who can help me with the soil resistivity measurement problem? Currently, the industry generally uses the quadrupole method to measure soil resistivity.

The core principle is: insert 4 electrodes (L) into the soil at equal distances, energize the two outermost electrodes, measure the current I, and then measure the voltage U of the two inner electrodes.

Soil resistance R=U/I, and finally calculate soil resistivity ρ=2πLR. The principle of this method is also recommended in the national standard. However, there is little information on this method, and only the principle is introduced.

Can anyone recommend a specific and feasible solution? The solution I tested is to use a 12V power supply to connect two external electrodes, and then the ADC measures the voltage and current of the two internal electrodes.

The result is too large to be realistic. I guess, but is it feasible to increase the voltage to 24V, 48V, etc.?

gmchen

"Use a 12V power supply to connect the two external electrodes, and then the ADC measures the voltage and current of the two internal electrodes"

How to measure current with only two inner electrodes?

qwqwqw2088

If 12V cannot be measured, increasing the voltage will definitely help

For reference, the four-probe resistivity tester for measuring metal and insulating materials is a device that has four metal probes arranged in a straight line and pressed on the semiconductor material with a certain pressure. A current I passes between two probes, and a potential difference V is generated between the other two probes.